CVE-2026-49973

Description

Hermes WebUI before version 0.51.358 contains an improper access control vulnerability that allows unauthenticated remote attackers to hijack initial setup by submitting the _set_password parameter to the settings API endpoint without any network origin restriction. Attackers on any reachable network can send a POST request to the settings endpoint during the first-run setup window to persist an arbitrary password hash, obtain a valid session cookie, and lock out the legitimate operator from their own instance.

References

• https://github.com/nesquena/hermes-webui/commit/1126e541325d401538f6a272a9c024c37d47ae08
• https://github.com/nesquena/hermes-webui/pull/3964
• https://github.com/nesquena/hermes-webui/pull/3973
• https://github.com/nesquena/hermes-webui/releases/tag/v0.51.358
• https://www.vulncheck.com/advisories/hermes-webui-unauthenticated-password-takeover-via-api-settings