Openclaw cli: OpenClaw: Hostname checks could treat trailing-dot hosts inconsistently (CVE-2026-53859)
Description
OpenClaw CLI versions from 2026.1.29 up to but not including 2026.5.28 have a vulnerability where hostname checks treat trailing-dot hosts inconsistently. This can allow requests with trailing-dot hostnames to bypass blocklist comparisons, potentially reaching destinations that operators intended to block. The vulnerability affects features that accept model- or workspace-derived URLs and depends on operator configuration and input trust levels. A patch is available starting with version 2026.5.26. Until patched, network-level blocking of private-network and metadata destinations is recommended, along with minimizing allowlists and disabling the affected feature if not needed.
CVSS v3.1
Score 6.5medium
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The OpenClaw CLI has a vulnerability (CVE-2026-53859) in hostname checking logic where hostnames with trailing dots are inconsistently handled. This inconsistency allows requests using trailing-dot hostnames to bypass blocklist checks in features that accept model- or workspace-derived URLs. The issue does not affect the trusted-operator model or authenticated components unless separate policies are crossed. The vulnerability is present in versions >=2026.1.29 and <2026.5.28 and is addressed in version 2026.5.26.
Potential Impact
If the affected feature is enabled and accessible, an attacker or lower-trust input could exploit the trailing-dot hostname inconsistency to reach destinations that should be blocked by hostname policies. The actual impact depends on the operator's configuration and whether untrusted inputs can reach the vulnerable path. The vulnerability can lead to unauthorized access to destinations that operators intended to block.
Mitigation Recommendations
A patch is available starting with OpenClaw CLI version 2026.5.26. Until systems are updated, operators should block private-network and metadata destinations at the proxy or network layer. Additionally, operators should keep channel and tool allowlists narrow, avoid sharing a Gateway between mutually untrusted users, and disable the affected feature when it is not needed.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BREW-openclaw-cli-CVE-2026-53859
- Osv Schema Version
- 1.7.3
- Ecosystems
- ["Homebrew"]
- Cvss Version
- 3.1
Threat ID: 6ac2458a12601ec6a3164116
Added to database: 10/04/2026, 12:24:42 UTC
Last enriched: 10/04/2026, 12:34:42 UTC
Last updated: 10/04/2026, 16:08:39 UTC
Views: 1
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