{"affected":[{"defaultStatus":"unaffected","ecosystem":"pypi","packageName":"headroom-ai","product":"Headroom","source":"CNA: VulnCheck","vendor":"Headroom Labs","versions":[{"lessThan":"0.36.1","status":"affected","version":"0","versionType":"semver"},{"status":"unaffected","version":"0.36.1","versionType":"semver"}]}],"cveId":"CVE-2026-77776","cwes":["CWE-639"],"description":"Headroom's LLM proxy derives the memory owner from the x-headroom-user-id request header. The header is read directly at several points in headroom/proxy/handlers/openai.py, including the chat completion and websocket paths, and nothing binds the value to the caller. A client can therefore name another user's identifier and read or write that user's stored LLM memory. The fix introduces a single resolve_memory_identity seam in headroom/proxy/identity.py that honors the header only for loopback or allowlisted callers and otherwise binds the identity to the proxy-token fingerprint or the operating system user. The pip console script binds 127.0.0.1 by default, but the reference docker-compose.yml ships --host 0.0.0.0 with published ports and no required HEADROOM_PROXY_TOKEN, which the server itself warns about at startup, so a deployment following the shipped compose exposes the affected data-plane routes to the network without authentication.","epss":{"date":"2026-11-08","percentile":0.49614,"score":0.00613},"exploits":[],"kev":null,"metrics":[{"score":9.1,"severity":"critical","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},{"score":9.3,"severity":"critical","source":"CNA: VulnCheck","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"}],"modifiedAt":1794146941029,"publishedAt":1787311371779,"references":[{"source":"CNA: VulnCheck","tags":["issue-tracking","patch"],"url":"https://github.com/headroomlabs-ai/headroom/pull/2207"},{"source":"CNA: VulnCheck","tags":["technical-description"],"url":"https://github.com/headroomlabs-ai/headroom/blob/v0.29.0/headroom/proxy/handlers/openai.py"},{"source":"CNA: VulnCheck","tags":["technical-description"],"url":"https://github.com/headroomlabs-ai/headroom/blob/v0.36.1/headroom/proxy/identity.py"},{"source":"CNA: VulnCheck","tags":["product"],"url":"https://github.com/headroomlabs-ai/headroom"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/headroom-proxy-treats-the-client-supplied-x-headroom-user-id-header-as-an-authenticated-identity"}],"remediation":[{"kind":"fix","source":"CNA: VulnCheck","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/headroomlabs-ai/headroom/pull/2207"}],"revision":"5227f425a8353edcc7dea99a46e88c82b53907de612ab480c08e452d2c911575","sources":[{"modifiedAt":1794146941029,"name":"CNA: VulnCheck","retrievedAt":1794151371891,"url":"https://www.cve.org/CVERecord?id=CVE-2026-77776"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794151400154,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-77776"}],"ssvc":{"assessedAt":1787347134351,"automatable":"yes","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"total"},"status":"published","title":"Headroom Proxy Treats the Client-Supplied x-headroom-user-id Header as an Authenticated Identity","updatedAt":1794151400154}