RCE in Nesquena Hermes-Webui
CVE-2026-49959
Hermes WebUI before version 0.51.311 contains a remote code execution vulnerability that allows authenticated attackers to execute arbitrary commands by placing malicious executable Git configuration in a workspace repository's .git/config file. Attackers can exploit Git subprocess invocations in api/workspace_git.py through vectors such as core.fsmonitor during git status, protocol.ext.allow with ext:: remotes during git fetch, credential.helper, core.askPass, core.gitProxy, or inherited environment variables including GIT_SSH_COMMAND to achieve arbitrary command execution on the host running the application.
Vulnerability class: Command Injection (OS Command Injection)
EPSS: 0.009 (59.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Nesquena Hermes-webui — versions 0
Weakness classification (CWE)
References
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (issue-tracking)
- disclosure@vulncheck.com (release-notes)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-49959?
- CVE-2026-49959 is a high-severity vulnerability in Nesquena Hermes-Webui, classified under OS Command Injection. CVSS score: 8.8/10. Published 2026-06-09.
- How severe is CVE-2026-49959?
- High severity. CVSS v3 base score is 8.8 out of 10.