What is CVE-2026-34511?

CVE-2026-34511 is a medium-severity vulnerability in Openclaw, classified under Use of Insufficiently Random Values. CVSS score: 5.3/10. Published 2026-04-03.

How severe is CVE-2026-34511?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Openclaw

CVE-2026-34511

OpenClaw before 2026.4.2 reuses the PKCE verifier as the OAuth state parameter in the Gemini OAuth flow, exposing it through the redirect URL. Attackers who capture the redirect URL can obtain both the authorization code and PKCE verifier, defeating PKCE protection and enabling token redemption.

EPSS: 0.002 (15.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N.

Affected products

Openclaw — versions 0, 2026.4.2

Weakness classification (CWE)

CWE-330 — Use of Insufficiently Random Values

References

disclosure@vulncheck.com (vendor-advisory, Vendor Advisory)
disclosure@vulncheck.com (Patch, patch)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2026-34511?: CVE-2026-34511 is a medium-severity vulnerability in Openclaw, classified under Use of Insufficiently Random Values. CVSS score: 5.3/10. Published 2026-04-03.
How severe is CVE-2026-34511?: Medium severity. CVSS v3 base score is 5.3 out of 10.