CVE-2026-34511Network attack vector

Token theft via reflected PKCE verifier

Published Apr 3, 2026 · Updated Apr 3, 2026

OAuth credential exposure in OpenClaw before 2026.4.2 allows attackers to redeem Gemini access tokens from captured redirect URLs. The Gemini OAuth URL builder assigns the secret PKCE verifier to the reflected state parameter, placing it beside the authorization code in the callback URL. Exploitation requires a user to complete the OAuth flow and an attacker to capture that redirect URL; the resulting token grants the associated Gemini access.

CVSS severity7.0
High
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OAuth credential exposure in OpenClaw before 2026.4.2 allows attackers to redeem Gemini access tokens from captured redirect URLs. The Gemini OAuth URL builder assigns the secret PKCE verifier to the reflected state parameter, placing it beside the authorization code in the callback URL. Exploitation requires a user to complete the OAuth flow and an attacker to capture that redirect URL; the resulting token grants the associated Gemini access.

The record

CVE
CVE-2026-34511
Published
Apr 3, 2026
Updated
Apr 3, 2026
Vendor
OpenClaw Foundation
Product
OpenClaw
Classifications
CWE-330, CWE-345, T1528
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 3, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <2026.4.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

OpenClaw Foundation · OpenClawversion=0 <2026.4.2

Published CVSS scores

7.0GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:H/SI:H/SA:N
6.0VulnCheckCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
5.9VulnCheckCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
5.9NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-330Use of Insufficiently Random Values
CWE-345Insufficient Verification of Data Authenticity
T1528Steal Application Access Token

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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