CVE-2026-53839
MEDIUM 6OpenClaw before 2026.5.7 contains a hostname validation vulnerability in retry endpoint checks that allows matching hostname prefixes instead of exact hostnames. Attackers can exploit this by crafting a hostname prefix resembling a trusted host to send authentication material to untrusted endpoints.
NO EXPLOITATION SIGNALS
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
0.3%chance of exploitation in 30 days · 18th percentile
○ In CISA KEV
○ Public exploit / PoC
Impact if exploited
6CVSS 4.0 · MEDIUM
- ConfidentialityHigh
- IntegrityNone
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
- ⚠Requirements: Specific conditions must be present
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-53839/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-53839/poc.json
Weakness (CWE)
- CWE-1023: Incomplete Comparison with Missing Factors
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Openclaw | Openclaw | < 2026.5.7 |
All CVSS metrics
- MEDIUM 6 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N - MEDIUM 6.5 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - MEDIUM 6 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - MEDIUM 6.5 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N