Unauthorized Matrix context injection via unchecked senders
Published Apr 28, 2026 · Updated Apr 28, 2026
Origin validation error in OpenClaw before 2026.3.31 allows remote attackers to inject excluded Matrix context via crafted replies. The Matrix room-message handler fetched thread-root and reply events into prompt context without checking their senders against effective room or group allowlists. Exploitation requires an allowlisted message to reference content from a blocked sender; the blocked content can then influence agent processing or be disclosed in context.
Summary
What happened
Origin validation error in OpenClaw before 2026.3.31 allows remote attackers to inject excluded Matrix context via crafted replies. The Matrix room-message handler fetched thread-root and reply events into prompt context without checking their senders against effective room or group allowlists. Exploitation requires an allowlisted message to reference content from a blocked sender; the blocked content can then influence agent processing or be disclosed in context.
The record
- CVE
- CVE-2026-41376
- Published
- Apr 28, 2026
- Updated
- Apr 28, 2026
- Vendor
- OpenClaw Foundation
- Product
- OpenClaw
- Classifications
- CWE-346, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 28, 2026CVE publishedPublication date reported by the CVE source.
- Apr 28, 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.
- Affected versionversion=0 <2026.3.31
What conditions does exploitation require?
What is affected?
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.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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