CVE-2026-34509Network attack vector

Unauthorized Teams replies via fail-open sender policy

Published Mar 31, 2026 · Updated Mar 31, 2026

Authorization bypass in OpenClaw before 2026.3.8 allows remote authenticated users to trigger replies in allowlisted Teams routes. The Microsoft Teams message handler treats an empty groupAllowFrom value as wildcard sender authorization when a team or channel route matches. A sender must belong to a matched Teams route; the flaw does not create default unauthenticated access and is limited to bot replies.

CVSS severityUnavailable
Unscored
EPSS probabilityUnavailable
No score available in this record
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

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Summary

What happened

Authorization bypass in OpenClaw before 2026.3.8 allows remote authenticated users to trigger replies in allowlisted Teams routes. The Microsoft Teams message handler treats an empty groupAllowFrom value as wildcard sender authorization when a team or channel route matches. A sender must belong to a matched Teams route; the flaw does not create default unauthenticated access and is limited to bot replies.

The record

CVE
CVE-2026-34509
Published
Mar 31, 2026
Updated
Mar 31, 2026
Vendor
OpenClaw Foundation
Product
OpenClaw
Classifications
CWE-289, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 31, 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 <2026.3.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OpenClaw Foundation · OpenClawversion=0 <2026.3.8

Published CVSS scores

No CVSS assessment is available in this record.

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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-289Authentication Bypass by Alternate Name
T1190Exploit Public-Facing Application

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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