SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-58123

Hermes WebUI before 0.51.788 contains an unauthenticated remote code execution vulnerability that allows remote attackers to execute arbitrary shell commands by accessing the embedded terminal API endpoints without credentials.

CRITICAL 9.3EPSS 4.65%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (4.65%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Hermes WebUI before 0.51.788 contains an unauthenticated remote code execution vulnerability that allows remote attackers to execute arbitrary shell commands by accessing the embedded terminal API endpoints without credentials. Attackers can create a session, attach a PTY shell, and write arbitrary commands through the terminal input endpoint to achieve full command execution as the server process user via four sequential unauthenticated HTTP requests.

CVSS 4.0
9.3 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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/M
EPSS
4.65% probability · 91th percentile
CISA KEV
Not listed
Weakness
CWE-306
Source
disclosure@vulncheck.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.