CVE-2026-34511
OAuth PKCE Bypass in OpenClaw Gemini Flow Exposes Tokens
Publication date: 2026-04-03
Last updated on: 2026-04-22
Assigner: VulnCheck
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| openclaw | openclaw | to 2026.4.2 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-330 | The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in OpenClaw versions before 2026.4.2, where the PKCE verifier is reused as the OAuth state parameter in the Gemini OAuth flow.
Because the PKCE verifier is exposed through the redirect URL, attackers who capture this URL can obtain both the authorization code and the PKCE verifier.
This defeats the protection normally provided by PKCE, allowing attackers to redeem tokens that should be protected.
How can this vulnerability impact me? :
An attacker who captures the redirect URL can obtain sensitive OAuth credentials, specifically the authorization code and PKCE verifier.
This enables the attacker to redeem tokens that grant access to protected resources, potentially leading to unauthorized access.