CVE-2026-91166CWE-297CWE-923

CVE-2026-91166

Medium · published September 21, 2026

CVSS v3.1
5.7
EPSS
0%
Percentile
11.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.7 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00218 · 11.6th percentile
Weaknesses
CWE-297 · Improper Validation of Certificate with Host Mismatch; CWE-923 · Improper Restriction of Communication Channel to Intended Endpoints
Published
2026-09-21T23:17Z
References (4)
EPSS history
Timeline
  • 23 SEP 03:49Z
    EPSS moved — → 0%
    epss
  • 21 SEP 18:53Z
    Warpgate: Web SSH stores a jump host's key against the target's address, so it validates as the target
    cvelistv5