{"id":"CVE-2026-55434","aliases":["GHSA-f5vp-w269-392g"],"title":"Coder vulnerable to denial of service via unbounded request body in AI Bridge provider endpoints","summary":"Coder vulnerable to denial of service via unbounded request body in AI Bridge provider endpoints","severity":"medium","cvss":6.5,"cwe":["CWE-770"],"vendor":"coder","product":"github.com/coder/coder/v2","ecosystem":"go","affected":["github.com/coder/coder/v2 >= 2.34.0, < 2.34.2","github.com/coder/coder/v2 >= 2.33.0, < 2.33.8"],"patched":["github.com/coder/coder/v2 2.34.2","github.com/coder/coder/v2 2.33.8"],"published":"2026-07-06","updated":"2026-07-06","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-f5vp-w269-392g","references":[{"url":"https://github.com/coder/coder/security/advisories/GHSA-f5vp-w269-392g"},{"url":"https://github.com/coder/coder/pull/26164"},{"url":"https://github.com/advisories/GHSA-f5vp-w269-392g"}],"tags":["ghsa","go"],"ingestedAt":"2026-07-06T21:45:52.952Z","epss":0.00552,"epssPercentile":0.4475,"slug":"CVE-2026-55434","body":"## Overview\n\n### Summary\n\nAI Bridge provider handlers read request bodies with `io.ReadAll` without a maximum size so an authenticated user with AI Bridge access could send an arbitrarily large body and exhaust memory.\n\n> **Note:** Exploitation requires authenticated access to the AI Bridge endpoints and the impact is limited to availability (denial of service).\n\n### Impact\n\nAn authenticated member-level user could POST a very large or chunked body to an AI Bridge provider endpoint such as `/api/v2/aibridge/anthropic/v1/messages`, growing heap memory until the operating system terminates the process. Because AI Bridge runs in-process with `coderd`, this crashes the entire control plane, including the API, workspace coordinator and DERP relay. It requires an authenticated user and the AI Bridge feature enabled.\n\n### Patches\n\nThe fix applies `http.MaxBytesReader` or an equivalent cap before reading provider and session request bodies. The affected AI Bridge provider endpoints exist only on the v2.33 and v2.34 lines. Earlier release lines are not affected.\n\nThe fix is available in the following releases:\n\n| Release line | Patched version |\n|---|---|\n| 2.34 | [v2.34.2](https://github.com/coder/coder/releases/tag/v2.34.2) |\n| 2.33 | [v2.33.8](https://github.com/coder/coder/releases/tag/v2.33.8) |\n\n### Workarounds\n\nNone.\n\n### Resources\n\n- Fix: #26164\n\n### Credits\n\nCoder would like to thank Anthropic's Security Team (ANT-2026-22443) for independently disclosing this issue!\n\n## Affected packages\n\n- `github.com/coder/coder/v2 >= 2.34.0, < 2.34.2`\n- `github.com/coder/coder/v2 >= 2.33.0, < 2.33.8`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/coder/coder/v2 2.34.2`\n- `github.com/coder/coder/v2 2.33.8`","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}