{"id":"GHSA-fg94-h982-f3mm","revision":"bf307c918548407883ec0faf50ce93f9","records":[{"revision":"bf307c918548407883ec0faf50ce93f9","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-fg94-h982-f3mm","aliases":["CVE-2026-54316"],"title":"Claude Code: Out-of-Band Data Exfiltration via Pre-Approved HuggingFace Domain in WebFetch","description":"Because the hostname huggingface.co was pre-approved as a bare hostname for the WebFetch tool, any path on that domain—including attacker-controlled model repositories—was auto-approved without a permission prompt or being subject to --allowedTools restrictions. An attacker able to inject untrusted content into a Claude Code context could direct it to issue WebFetch requests against attacker-controlled repository files (e.g. /resolve/main/config.json), which HuggingFace counts as downloads server-side, creating a covert out-of-band channel for encoding and exfiltrating data Claude can access such as files, environment variables, or command output. Reliably exploiting this required the ability to add untrusted content into a Claude Code context window. Users on standard Claude Code auto-update have received this fix already; users performing manual updates are advised to update to the latest version.\n\nThank you to hackerone.com/novee for reporting this issue.","state":0,"publishedAt":"2026-06-17T18:06:06+00:00","modifiedAt":"2026-07-20T21:15:27.4623884+00:00","affected":[{"ecosystem":"npm","name":"@anthropic-ai/claude-code","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0.2.54"},{"kind":"fixed","version":"2.1.163"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","score":null,"severity":null},{"system":"CVSS_V4","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/anthropics/claude-code/security/advisories/GHSA-fg94-h982-f3mm","https://nvd.nist.gov/vuln/detail/CVE-2026-54316","https://github.com/anthropics/claude-code"],"sourceUrl":"https://github.com/advisories/GHSA-fg94-h982-f3mm","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-fg94-h982-f3mm","identifiers":["GHSA-fg94-h982-f3mm","CVE-2026-54316"]},"retained":false,"historicalAffected":[]}],"coverage":[]}