Cloudflare AI responses expose other customers' request data in 155 cases
From 27 August to 9 September, 155 responses from the GLM-5.3 model on Cloudflare Workers AI included other customers' recent request data. The problem, caused by a combination of a context setting mismatch and a flaw in SGLang cache handling, has been fixed. No evidence of deliberate abuse was found.
Key facts
- Affected organisation
- Cloudflare
- Incident type
- Data breach
- Occurred / detected
- 2026-08-27
- Scale of damage
- Other customers' request data exposed in 155 AI responses
- Cause / method
- Context setting mismatch and a flaw in SGLang cache handling
- Location
- United States
If your data was exposed
- Don’t tap links in texts, calls or emails that mention this incident and offer compensation, refunds or breach checks. Check directly on the organisation’s official website or app.
Timeline
- The period began in which the GLM-5.3 model on Workers AI included other customers' request data in responses.
- The period of request data exposure, which affected a total of 155 responses, ended.
- Cloudflare disclosed that the flaw had been fixed and that its investigation found no evidence of deliberate abuse.
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The summary and key facts are written by AI from related reports and may contain errors. Check the original articles and the organisation’s official statements for accurate details.