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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
OpenClaw OpenClaw unaffected
Version Status Constraints
0 affected < 2026.3.31
2026.3.31 unaffected —

No data.

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Project Subscriptions

Vendors Products
Openclaw Subscribe
Openclaw Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/openclaw/openclaw/commit/ad77666054651c1fd77b1dc60fd6a8db6600a29a cve-icon cve-icon
https://github.com/openclaw/openclaw/security/advisories/GHSA-37v6-fxx8-xjmx cve-icon cve-icon
https://www.vulncheck.com/advisories/openclaw-webhook-replay-detection-bypass-via-base64-signature-re-encoding cve-icon cve-icon
History

Thu, 23 Apr 2026 22:15:00 +0000

Type Values Removed Values Added
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.
Title OpenClaw < 2026.3.31 - Webhook Replay Detection Bypass via Base64 Signature Re-encoding
First Time appeared Openclaw
Openclaw openclaw
Weaknesses CWE-294
CPEs cpe:2.3:a:openclaw:openclaw:*:*:*:*:*:node.js:*:*
Vendors & Products Openclaw
Openclaw openclaw
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

cvssV4_0

{'score': 6.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-04-23T21:58:11.440Z

Reserved: 2026-04-20T14:07:26.648Z

Link: CVE-2026-41351

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-23T22:16:42.160

Modified: 2026-04-23T22:16:42.160

Link: CVE-2026-41351

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses