C

Cloudflare

Secures websites and runs apps on its network

Product Manager Intern

Summer 2027Updated
No salary listed
Internship
Bachelor's, Master's
London, UK
In PersonIn-office 3–5 days per week in London; full-time, in-person expectations during standard business hours.
ProductTechnical Product Management

About the job

Requirements
  • Currently pursuing a Bachelor's or Master's degree in Computer Science, Human-Computer Interaction, Business, Engineering, or a related field.
  • Have technical literacy to understand architectural concepts and empathize with developer workflows.
  • Commit to a full-time, 40-hour-per-week, 12-week internship.
  • Work in the London office 3–5 days per week; remote and part-time applicants are not considered.
  • Be available during standard business hours, typically 9:00 AM–6:00 PM, and not be enrolled in classes that conflict with the internship term.
Responsibilities
  • Conduct user research and competitive analysis to understand user needs and market trends, identifying pain points and opportunities to improve the tools.
  • Collaborate with engineering, design, and product leaders to bring product visions to life and ensure features are built to specification, meet user expectations, and solve technical problems at scale.
  • Help define success metrics and ensure launched features are technically sound, create measurable business value, and solve real-world user problems.
  • Analyze challenges proactively, balance technical feasibility with user needs, and turn market constraints into opportunities for innovation and growth.
  • Own a project focused on improving products, enhancing the user experience, and driving development of key features.
Desired Qualifications
  • Have familiarity with networking, security, or Zero Trust concepts, such as TCP/IP, HTTP, or DNS.
  • Have hands-on experience with developer tools, APIs, or personal projects using Cloudflare products, such as Cloudflare for Students.
  • Have previous experience writing product specifications, building wireframes, or conducting user research.
  • Have basic coding ability or familiarity with command-line tools and developer workflows.

About the company

Cloudflare operates a network that protects websites, delivers online content and runs applications closer to their users. Businesses connect websites and internal systems to its services to filter malicious traffic, control access and improve performance, with security and computing running on shared infrastructure. Developers combine application code, object storage and databases with the network used for content delivery and traffic protection. Cloudflare earns revenue from subscriptions and usage charges, with free plans for basic features and negotiated contracts for larger organizations. Cloudflare was founded in 2009 and is headquartered in San Francisco, California.

Company Size

1,001-5,000

Company Stage

IPO

Headquarters

San Francisco, California

Founded

2009

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Simplify's Take

What believers are saying

  • Demand is growing: Cloudflare reported $696 million revenue, up 36%, for the June 2026 quarter.
  • New parents get paid bonding time: qualifying Cloudflare employees receive up to sixteen paid weeks globally.
  • Attack protection has predictable billing: Cloudflare provides unmetered DDoS mitigation across all plans, including its free tier.

What critics are saying

  • Employees faced a major workforce reduction: Cloudflare announced more than 1,100 global job cuts in May 2026.
  • One software fault spread widely: Cloudflare's bot-management configuration broke core network traffic in November 2025.
  • Free users still incur costs: most Cloudflare customers pay nothing, while the company bears incremental network expenses.

What makes Cloudflare unique

  • Services share network locations: Cloudflare runs its security and delivery stack in every data center.
  • R2 makes outbound bandwidth free: Cloudflare charges for storage and requests, without fees for direct Internet data transfers.
  • Workers handles deployment and scaling: developers publish apps across Cloudflare's global network without managing servers.

Help us improve and share your feedback! Did you find this helpful?

Benefits

  • Competitive salaries
  • Take-what-you-need paid vacation policy
  • Comprehensive health plans and benefits
  • Paid maternity and paternity leave
  • Commuter and ride share options
  • Returnships

Growth & Insights and Company News

6 month growth

7%

1 year growth

8%

2 year growth

7%
EarnQA
Oct 27th, 2026
The AI spam flood behind A difficult bug hunting search.

The AI spam flood behind A difficult bug hunting search. Cloudflare says a hosted AI model returned 155 responses containing other customers' data. A separate audit highlights the growing burden of AI-generated bug reports. Up next. Published on 27 October 2026 AI This post was created with the assistance of artificial intelligence (AI). Buying for a business? Offer from Amazon Get business pricing on monitors, keyboards and dev gear * Business-only prices and quantity discounts * Tax-exempt purchasing * Multiple users, one account, clear invoices As an affiliate, EarnQA, Inc. earn on qualifying purchases. Cloudflare reported that its hosted GLM-5.3 model returned 155 responses containing data from other customers' requests between August 27 and September 9, 2026. In a separate security-audit example, Jump Crypto says AI agents likely found or wrote nearly all reports submitted to a Firedancer contest, leaving reviewers to sort 809 submissions into 127 unique findings. Cloudflare disclosed October 26 that its hosted GLM-5.3 model returned 155 responses containing data from other customers' requests over a 14-day period. A separate Jump Crypto audit contest offers a contrasting security problem: the company received 809 submissions that it says were reduced to 127 unique findings, with AI agents likely responsible for nearly all the reports. Together, the cases show how AI can create both security risks in deployed services and more work for the people reviewing bug reports. Cloudflare traced the leak, which ran from August 27 to September 9, to a mismatch in its configuration combined with a bug in the open-source inference engine SGLang. The affected endpoint was its hosted @cf/zai-org/glm-5.3 model on Workers AI. According to Cloudflare, only prompts longer than 681,280 tokens could trigger the issue, despite the service advertising a context window of 1,048,576 tokens. Discover more Audit Quality Try Cloud Tools Try Dev Tools The incident involved the model's key-value cache, a store of intermediate data used to generate responses. Cloudflare said cache pages were not cleared between requests, a practice it described as common and useful for performance. When a too-long prompt was rejected in one part of its split inference setup, a queue in another part checked whether the request had finished but not whether it had been rejected. That allowed decoding to read cache pages that still contained data from other requests. Cloudflare says the affected responses returned HTTP 200 and could appear coherent. Security researcher Gadi Evron of Knostic reported the issue through HackerOne on September 8. Cloudflare says it took the model offline 38 minutes after declaring an incident and restored a fixed version later that evening. It found no evidence of deliberate exploitation, and says the affected requests appeared consistent in timing and volume with ordinary long-context use. Separately, Jump Crypto's $1 million Firedancer audit contest drew reports from 162 researchers. Jump says those 809 reports amounted to 127 unique findings and believes AI agents found or wrote nearly every submission. At a glance report When: Cloudflare published its incident repor... The development A Cloudflare incident report and a Jump Crypto audit contest illustrate two different security effects of AI: a customer-data leak in hosted inference and a surge of reports that are costly to review. Thorsten Meyer AI Cloudflare Workers AI · GLM-5.3 Infographic 01 · Cross-request KV cache exposure How a long prompt read someone else's data. A memory pool smaller than the advertised context window, plus an engine bug that let rejected requests through, made one hosted model attend over other customers' leftover pages. 155 responses that contained other customers' data 14 days exposure window, 27 Aug to 9 Sep 2026 38 min from declaring the incident to taking the model offline none evidence of deliberate exploitation, per Cloudflare The mismatch. tokens; Cloudflare knew before launch and expected an error * Context windowadvertised1,048,576 * KV pool before the fixprefill GPUs681,280 * KV pool after the fixabout twice the window~2.04 M Only prompts longer than 681,280 tokens could reach the faulty path. The eight pages. Cloudflare's own example of one over-long request P0 written now P1 left over P2 left over P3 left over P4 left over P5 left over P6 left over P7 left over * Decode reserves 8 pages for the long prompt. * Prefill rejects it and swaps in a one-token placeholder... * ...but the rejected request still passes the handoff checks. * Prefill writes one page; decode reads all eight. * The client gets HTTP 200 and a coherent reply, partly built on someone else's data. Why pages hold old data. speed trade-off * GPU memory is a shared pool of fixed-size pages * Pages are not zeroed between requests; the next one overwrites * Bookkeeping is the only wall between customers The fix. 9 Sep, 19:40 UTC * Pool resized so every valid prompt fits * Engine retires rejected requests before any memory transfer * Upstream: SGLang v0.5.20 to v0.5.22; operators should run v0.5.22+ Still open. not in the report * Whether and how affected customers were notified * How many customers' requests contributed the leaked data * What kind of data it was Two costs of ai-assisted security. The Cloudflare incident matters because it involved customer data crossing request boundaries in a hosted AI service. A customer submitting an unusually long prompt could receive text associated with another customer's request. Cloudflare's report gives a count of affected responses and a technical explanation, but does not state how many customers were affected or describe how they were notified. The audit example points to a different pressure on security teams: generating bug reports has become cheaper, but validating, deduplicating and investigating them still takes human time. Jump's contest figures do not establish that AI-generated reports were invalid; the company's reported 127 unique findings came from 809 submissions. But the gap between submissions and unique findings shows why raw report volume is a poor measure of useful security work. For service operators, the leak underscores the need to test what a model returns - not just whether an inference request completes successfully. For bounty programs and researchers, the challenge is maintaining useful disclosure channels when automated tools can produce reports at scale.

ONE2CRYPTO
Oct 27th, 2026
How A KV cache leak can put an AI answer in the wrong session.

How A KV cache leak can put an AI answer in the wrong session. Cloudflare says its hosted GLM-5.3 model returned 155 responses containing other customers' data after a configuration mismatch and SGLang bug. Up next. Published on 27 October 2026 AI This post was created with the assistance of artificial intelligence (AI). Before you order Offer from Amazon Get hardware and tech essentials delivered free with Prime * Fast, free delivery on millions of items * Prime Video, Amazon Music and more included * Member-only deals all year As an affiliate, One2crypto earn on qualifying purchases. Cloudflare's incident report says its hosted GLM-5.3 model returned 155 responses containing text from other customers' requests between Aug. 27 and Sept. 9, 2026. The issue required prompts longer than 681,280 tokens and stemmed from a Cloudflare configuration mismatch combined with a bug in the SGLang inference engine. Cloudflare says it found no evidence of deliberate exploitation; its report does not explain how affected customers were notified. Cloudflare disclosed that its hosted GLM-5.3 model returned 155 responses containing text from other customers' requests during a 14-day period, after a configuration mismatch and a bug in the SGLang inference engine caused parts of GPU memory to be read across sessions. The company says the issue affected only prompts longer than 681,280 tokens and that it found no evidence of deliberate exploitation. In an incident report published Oct. 26, Cloudflare said the affected responses occurred between Aug. 27 and Sept. 9. Security researcher Gadi Evron of Knostic reported the issue through Cloudflare's HackerOne program on Sept. 8, saying very long prompts to the hosted endpoint sometimes returned text belonging to other users' sessions. Cloudflare counted 155 affected responses after excluding its own tests and the researcher's requests. The incident required two faults to coincide. Cloudflare configured the model with a 1,048,576-token context window, but the memory pool used to hold the prompt's KV cache could store only 681,280 tokens. The company expected oversized requests to produce an error. A bug in SGLang, however, let rejected requests continue through parts of Cloudflare's split prefill-and-decode system rather than stopping them. Cloudflare said the decode stage had reserved memory pages for the full prompt, while the prefill stage wrote only a one-token placeholder. The remaining pages could still contain other customers' prompts and partial generations. As a result, some responses were returned with an HTTP 200 status instead of an error. Cloudflare said it took the model offline 38 minutes after declaring an incident and restored a fixed version that evening. At a glance report When: Incident ran Aug. 27-Sept. 9, 2026; Clo... The development Cloudflare published an incident report describing a cross-customer data leak in its hosted GLM-5.3 service caused by a KV cache configuration mismatch and an SGLang bug. Crypto market snapshot Fear & Greed Index 48/100 - Neutral Bitcoin BTC $79,860 0.5% Ethereum ETH $2,316 0.5% Tether USDT $0.9987 0.1% BNB BNB $738.3 0.0% XRP XRP $1.3 1.1% USDC USDC $0.9994 0.0% Solana SOL $100.12 1.2% TRON TRX $0.3273 1.0% Live data · CoinGecko · alternative.me (24h change) Thorsten Meyer AI Cloudflare Workers AI · GLM-5.3 Infographic 01 · Cross-request KV cache exposure How a long prompt read someone else's data. A memory pool smaller than the advertised context window, plus an engine bug that let rejected requests through, made one hosted model attend over other customers' leftover pages. 155 responses that contained other customers' data 14 days exposure window, 27 Aug to 9 Sep 2026 38 min from declaring the incident to taking the model offline none evidence of deliberate exploitation, per Cloudflare The mismatch. tokens; Cloudflare knew before launch and expected an error * Context windowadvertised1,048,576 * KV pool before the fixprefill GPUs681,280 * KV pool after the fixabout twice the window~2.04 M Only prompts longer than 681,280 tokens could reach the faulty path. The eight pages. Cloudflare's own example of one over-long request P0 written now P1 left over P2 left over P3 left over P4 left over P5 left over P6 left over P7 left over * Decode reserves 8 pages for the long prompt. * Prefill rejects it and swaps in a one-token placeholder... * ...but the rejected request still passes the handoff checks. * Prefill writes one page; decode reads all eight. * The client gets HTTP 200 and a coherent reply, partly built on someone else's data. Why pages hold old data. speed trade-off * GPU memory is a shared pool of fixed-size pages * Pages are not zeroed between requests; the next one overwrites * Bookkeeping is the only wall between customers The fix. 9 Sep, 19:40 UTC * Pool resized so every valid prompt fits * Engine retires rejected requests before any memory transfer * Upstream: SGLang v0.5.20 to v0.5.22; operators should run v0.5.22+ Still open. not in the report * Whether and how affected customers were notified * How many customers' requests contributed the leaked data * What kind of data it was How shared GPU memory crossed sessions. The incident shows how a failure in inference-engine bookkeeping can expose information even when the underlying AI model is not itself at fault. KV cache data is temporary working memory created as a model processes a prompt. In this setup, memory pages were reused between requests without being cleared; the system relied on software tracking to prevent one request from reading pages associated with another. For customers, the concern is that an answer can appear coherent and arrive successfully while including material from a different session. Cloudflare said the affected responses were associated with exceptionally long prompts, which narrows the reported condition, but the report does not establish what specific customer information appeared in each response or whether recipients recognized the material as foreign. The episode also highlights the need to test output correctness and isolation, not just response codes and system performance. The disclosure comes alongside a wider challenge for security programs: AI tools can generate large volumes of bug reports, making it harder to identify valid findings. The source account cites Jump Crypto's Firedancer audit contest, where 809 reports from 162 researchers were reduced to 127 unique findings; Jump believes AI agents found or wrote nearly every submission. That separate example does not establish a connection to Cloudflare's incident, but it illustrates the pressure on teams to review security findings while also investigating vulnerabilities.

ForkLog
Oct 24th, 2026
Cloudflare introduces post-quantum encryption key protection.

Cloudflare introduces post-quantum encryption key protection. Cloudflare's GeoKey Manager beta restricts key access by region. Cloudflare has launched a closed beta of the new version of GeoKey Manager, which restricts decryption key access to selected geographic regions. The solution employs a hybrid scheme of ML-KEM-768 and X25519 to guard against potential quantum computer attacks. A public release is scheduled for the first quarter of 2027. Found a mistake in the text? Select it and press CTRL+ENTER

Industry Events
Oct 24th, 2026
Cloudflare Launches Post-Quantum GeoKey Manager with Hybrid ML-KEM-768 Encryption for Regional data sovereignty.

Cloudflare Launches Post-Quantum GeoKey Manager with Hybrid ML-KEM-768 Encryption for Regional data sovereignty. Cloudflare has launched its Post-Quantum GeoKey Manager in closed beta, integrating NIST-standardized post-quantum cryptography to enforce strict geographical boundaries on customer private key access. This new system protects sensitive enterprise data against "Harvest Now, Decrypt Later" attacks and helps satisfy regional data sovereignty mandates. General availability is expected in Q1 2027. The post Cloudflare Launches Post-Quantum GeoKey Manager with Hybrid ML-KEM-768 Encryption for Regional By Quantum Computing Report Got news to share with the events industry? More in Quantum Tech & Cryptography. Related insights. Relevant events. Events in Quantum Tech & Cryptography

OVFILE
Oct 22nd, 2026
Quad9 to exit France following Paris court penalty over pirate tennis stream blocks.

Quad9 to exit France following Paris court penalty over pirate tennis stream blocks. 2 days ago - 22 October 2026 Ammar Sabilarrohman OvFile Reporter Swiss non-profit DNS resolver Quad9 has announced it is pulling out of France entirely after a Paris court ordered financial penalties over the organization's refusal to block domains broadcasting unauthorized tennis streams. Starting November 24, Quad9 will officially stop serving users in France, making it the second major public DNS resolver to abandon the country over escalating website-blocking mandates. The decision arrives in the wake of a legal battle initiated by sports broadcaster beIN Sports, which targeted Quad9 for failing to comply with a May court order requiring the blocking of pirate domains. While beIN initially demanded exorbitant daily penalties reaching up to €580,000 for non-compliance, the Paris court ultimately ruled on a lower penalty structure, setting the fine at €1,000 per day. Although significantly reduced from the broadcaster's original request, the penalty still presented an untenable financial burden for the privacy-focused foundation, particularly when compounded by roughly 20 other pending blocking cases across the country. Earlier this month, representatives for Quad9 informed reporters that the foundation was actively weighing its future in France, explicitly leaving open the possibility of a complete market withdrawal. Yesterday's ruling cemented that trajectory, prompting the Swiss-based organization to publish a definitive "Au revoir, France" statement confirming that it will no longer offer recursive DNS resolution services to internet users within French borders as of November 24. €1,000 a Day and the Burden of Compliance. The Paris Judicial Court ordered Quad9 to implement a blocking directive initially issued in May, which has since expanded to encompass 58 distinct domain names. Failure to comply would trigger a penalty of €1,000 per day. While beIN had pushed for a rate of €10,000 per day for every individual domain that remained accessible through Quad9's network, the court consolidated the figure into a single daily penalty of €1,000 running until the blocking measures expire on November 14. Quad9 calculated that this period alone accumulates to approximately €24,000 in direct fines, excluding the foundation's mounting legal expenses. In its legal reasoning, the court emphasized Quad9's own admissions. According to the judicial panel, the foundation was obligated to make reasonable efforts to restrict access to the designated domain names but deliberately chose to take zero action. This approach contrasted sharply with the outcomes of similar recent legal challenges involving other network intermediaries. Earlier this month, the same Paris court rejected penalty requests filed by beIN against Cloudflare and several prominent virtual private network (VPN) providers. Those entities had successfully implemented blocks on at least a portion of the targeted domains, a measure the court deemed a sufficient manifestation of reasonable effort. A similar outcome occurred in September when Canal+ lost a parallel penalty bid against Cloudflare regarding its 1.1.1.1 resolver. Quad9, conversely, maintained a strict policy of non-compliance, confirming in court submissions that it had not blocked a single domain on the list. Leaving France on principle. For Quad9, the dispute extends far beyond monetary fines or legal expenditure. The foundation operates under the core philosophy that recursive DNS resolution should remain a neutral public utility, fundamentally untouched by commercial or judicial alterations. In a formal statement addressing the controversy, Quad9 articulated its stance on data integrity, explaining that the organization categorically refuses to alter or misrepresent DNS responses in a manner contrary to user expectations. The foundation further noted a technical barrier inherent to its infrastructure: because its free service operates globally without requiring user registration, there is no reliable method to isolate and apply filtering exclusively to users physically located in France. While complying with the court order would technically require blocking the specified domains for all users worldwide - thereby satisfying French jurisdiction by casting a global net - Quad9 flatly rejected the notion of enforcing a local French court mandate upon internet users across the globe. When evaluating how it will technically cease service for French users, Quad9 admitted that all available methods are imperfect. Furthermore, the foundation argues that regional DNS-level blocking is largely ineffective as an anti-piracy tool. Determined users can easily bypass the restrictions by switching to any of the thousands of alternative open DNS resolvers available online. Describing the futility of the measure, the foundation compared the mandate to holding a single piece of newspaper in front of a stadium crowd to block their view of a concert. Mounting legal pressure and future outlook. The catalyst for Quad9's departure was not isolated to the immediate conflict with beIN Sports. The foundation faces approximately 20 other pending court cases in France centered around similar site-blocking demands. Executives concluded that even if individual penalties appear manageable in isolation, the cumulative weight of ongoing and future litigation would ultimately bankrupt the non-profit entity. "Quad9 cannot survive the accumulation of penalties yet to be assessed in 20 other pending cases, nor those of future cases similar to the one brought by beIN," the foundation stated, underscoring the impossibility of maintaining operations under such regulatory exposure. Quad9 is not the pioneer of this retreat. In 2024, OpenDNS similarly suspended its services in France following a piracy-blocking order brought by broadcaster Canal+. Beyond operational survival, Quad9's leadership views the broader trend of judicial blocking mandates as a dangerous precedent for digital rights and infrastructure. The foundation warns that legal mechanisms ostensibly established to protect specific commercial content rights can easily expand in scope. In the words of the organization, once the tools of censorship are constructed, they are rarely deployed sparingly or justly. While an appeal remains pending and the foundation has vowed to continue its broader fight against court-ordered DNS restrictions, its immediate chapter in France is drawing to a close. French users relying on the service have until November 24 to transition to alternative DNS providers before Quad9 formally exits the jurisdiction. Related topics.