{"id":"GHSA-99hj-44vg-hfcp","revision":"f9a3288ee1f645d1b74d713479a49da6","records":[{"revision":"f9a3288ee1f645d1b74d713479a49da6","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GHSA-99hj-44vg-hfcp","aliases":["CVE-2026-26061","GO-2026-4889"],"title":"Fleet's unbounded request body read allows remote Denial of Service","description":"### Summary\n\nFleet contained multiple unauthenticated HTTP endpoints that read request bodies without enforcing a size limit. An unauthenticated attacker could exploit this behavior by sending large or repeated HTTP payloads, causing excessive memory allocation and resulting in a denial-of-service (DoS) condition.\n\n### Impact\n\nAn unauthenticated attacker could cause the Fleet server process to exhaust available memory and restart by sending oversized or repeated HTTP requests to affected endpoints.\n\nThis vulnerability impacts **availability only**. There is:\n\n- No exposure of sensitive data\n- No authentication bypass\n- No privilege escalation\n- No integrity impact\n\n### Workarounds\n\nIf upgrading immediately is not possible, the following mitigations can reduce exposure:\n\n- Apply request body size limits at a reverse proxy or load balancer (e.g., NGINX, Envoy).\n- Restrict network access to endpoints to known IP ranges where feasible.\n- Monitor memory usage and restart frequency for abnormal patterns.\n\n### For More Information\n\nIf there are any questions or concerns about this advisory, please contact us at:\n\nEmail Fleet at [security@fleetdm.com](mailto:security@fleetdm.com)\n\n### Credits\n\nFleet thanks @fuzzztf for responsibly reporting this issue.","state":0,"publishedAt":"2026-03-27T18:17:42+00:00","modifiedAt":"2026-04-02T21:26:16.4626483+00:00","affected":[{"ecosystem":"Go","name":"github.com/fleetdm/fleet/v4","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"4.43.5-0.20260113202849-bbc1aef2987d"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V4","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"HIGH"}],"references":["https://github.com/fleetdm/fleet/security/advisories/GHSA-99hj-44vg-hfcp","https://nvd.nist.gov/vuln/detail/CVE-2026-26061","https://github.com/fleetdm/fleet"],"sourceUrl":"https://github.com/advisories/GHSA-99hj-44vg-hfcp","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-99hj-44vg-hfcp","identifiers":["GHSA-99hj-44vg-hfcp","CVE-2026-26061","GO-2026-4889"]},"retained":false,"historicalAffected":[]}],"coverage":[]}