Vulnerability in Warp-Tech Warpgate
CVE-2026-91166
Warpgate is an open source SSH, HTTPS and MySQL bastion host for Linux. From 0.25.0 until 0.27.6, the browser SSH path in warpgate-web-ssh/src/manager.rs handles RCEvent::HostKeyUnknown without the presenting hop identity and instead passes ssh_options.host and ssh_options.port for the final target to KnownHosts::trust. In Prompt and AutoAccept modes, a jump host key can therefore be stored for the target address. A machine later presenting the jump host key at the target address can be accepted as the target, allowing interception of user traffic and a newly issued certificate when certificate authentication is used. The native SSH path is unaffected because it tracks each hop separately. This issue is fixed in version 0.27.6.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (12.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Warp-Tech Warpgate — versions >= 0.25.0, < 0.27.6
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-91166?
- CVE-2026-91166 is a medium-severity vulnerability in Warp-Tech Warpgate, classified under Improper Validation of Certificate with Host Mismatch. CVSS score: 5.7/10. Published 2026-09-21.
- How severe is CVE-2026-91166?
- Medium severity. CVSS v3 base score is 5.7 out of 10.