CVE-2026-41351

MEDIUM

OpenClaw < 2026.3.31 - Webhook Replay Detection Bypass via Base64 Signature Re-encoding

Title source: cna
STIX 2.1

Description

OpenClaw before 2026.3.31 contains a replay detection bypass vulnerability in webhook signature handling that treats Base64 and Base64URL encoded signatures as distinct requests. Attackers can re-encode Telnyx webhook signatures to bypass replay detection while maintaining valid signature verification.

References (3)

Core 3
Core References
Third Party Advisory third-party-advisory
VulnCheck Advisory: OpenClaw < 2026.3.31 - Webhook Replay Detection Bypass via Base64 Signature Re-encoding
https://www.vulncheck.com/advisories/openclaw-webhook-replay-detection-bypass-via-base64-signature-re-encoding
Vendor Advisory vendor-advisory
GitHub Security Advisory (GHSA-37v6-fxx8-xjmx)
https://github.com/openclaw/openclaw/security/advisories/GHSA-37v6-fxx8-xjmx

Scores

CVSS v3 5.3
EPSS 0.0025
EPSS Percentile 16.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-294
Status published
Products (4)
npm/openclaw 0 - 2026.3.31npm
OpenClaw/OpenClaw < 2026.3.31
openclaw/openclaw < 2026.3.31
OpenClaw/OpenClaw 2026.3.31
Published Apr 23, 2026
Tracked Since Apr 24, 2026