{"id":"CVE-2026-59157","state":"PUBLISHED","title":"webhookd: Unrestricted HTTP Header to Shell Variable Injection","description":"webhookd is a minimalist webhook server that triggers shell scripts and external processes through HTTP requests. Prior to 1.22.0, webhookd deployments without htpasswd authentication forwarded all incoming HTTP headers through HTTPParamsToShellVars in pkg/api/index.go into the hook script environment without an allowlist. When an upstream reverse proxy did not strip a client-supplied X-WebAuthn-User header and a hook script trusted that variable for identity or privilege, a remote unauthenticated attacker could spoof another user, bypass script security controls, and access or modify resources available to the impersonated identity. This issue is fixed in version 1.22.0.","publishedAt":"2026-09-15T15:46:35.418Z","updatedAt":"2026-09-16T15:38:42.407Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["ncarlier webhookd"],"affected":[{"vendor":"ncarlier","product":"webhookd","versions":[{"version":"< 1.22","status":"affected"}]}],"references":["https://github.com/ncarlier/webhookd/security/advisories/GHSA-v25g-mvwr-f5fp","https://github.com/ncarlier/webhookd/pull/121","https://github.com/ncarlier/webhookd/commit/5ac66677bf7224191f1dfc51a875b09187d10beb","https://github.com/ncarlier/webhookd/releases/tag/v1.22.0"],"weaknesses":["CWE-290","CWE-807"],"ingestedAt":"2026-10-29T20:12:32.778Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/59xxx/CVE-2026-59157.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-59157","state":"PUBLISHED","datePublished":"2026-09-15T15:46:35.418Z","dateUpdated":"2026-09-16T15:38:42.407Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-02T16:50:27.887Z"},"containers":{"cna":{"title":"webhookd: Unrestricted HTTP Header to Shell Variable Injection","descriptions":[{"lang":"en","value":"webhookd is a minimalist webhook server that triggers shell scripts and external processes through HTTP requests. Prior to 1.22.0, webhookd deployments without htpasswd authentication forwarded all incoming HTTP headers through HTTPParamsToShellVars in pkg/api/index.go into the hook script environment without an allowlist. When an upstream reverse proxy did not strip a client-supplied X-WebAuthn-User header and a hook script trusted that variable for identity or privilege, a remote unauthenticated attacker could spoof another user, bypass script security controls, and access or modify resources available to the impersonated identity. This issue is fixed in version 1.22.0."}],"affected":[{"vendor":"ncarlier","product":"webhookd","versions":[{"version":"< 1.22","status":"affected"}]}],"references":[{"url":"https://github.com/ncarlier/webhookd/security/advisories/GHSA-v25g-mvwr-f5fp","name":"https://github.com/ncarlier/webhookd/security/advisories/GHSA-v25g-mvwr-f5fp","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/ncarlier/webhookd/pull/121","name":"https://github.com/ncarlier/webhookd/pull/121","tags":["x_refsource_MISC"]},{"url":"https://github.com/ncarlier/webhookd/commit/5ac66677bf7224191f1dfc51a875b09187d10beb","name":"https://github.com/ncarlier/webhookd/commit/5ac66677bf7224191f1dfc51a875b09187d10beb","tags":["x_refsource_MISC"]},{"url":"https://github.com/ncarlier/webhookd/releases/tag/v1.22.0","name":"https://github.com/ncarlier/webhookd/releases/tag/v1.22.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"LOW","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-290","lang":"en","description":"CWE-290: Authentication Bypass by Spoofing","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-807","lang":"en","description":"CWE-807: Reliance on Untrusted Inputs in a Security Decision","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-15T15:46:35.418Z"},"source":{"advisory":"GHSA-v25g-mvwr-f5fp","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-16T15:38:31.622911Z","id":"CVE-2026-59157","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-16T15:38:42.407Z"}}]}}}