CVE-2026-59157

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/ncarlier/webhookd/commit/5ac66677bf7224191f1dfc51a875b09187d10beb
https://github.com/ncarlier/webhookd/pull/121
https://github.com/ncarlier/webhookd/releases/tag/v1.22.0
https://github.com/ncarlier/webhookd/security/advisories/GHSA-v25g-mvwr-f5fp

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-15 16:17

NVD link : CVE-2026-59157

Mitre link : CVE-2026-59157

CVE.ORG link : CVE-2026-59157

JSON object : View

Products Affected

No product.

CWE

CWE-290

Authentication Bypass by Spoofing

CWE-807

Reliance on Untrusted Inputs in a Security Decision

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