CVE-2026-58122: critical vulnerability in nesquena hermes-webui
Hermes WebUI < 0.51.307 Authentication Bypass via X-Forwarded-For Header Spoofing
Published · Updated
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28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.3epss 0.4%
Hermes WebUI before 0.51.307 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to circumvent local-origin IP restrictions on onboarding endpoints by supplying a spoofed X-Forwarded-For header with a loopback address. Attackers can exploit this bypass to perform server-side request forgery against internal services including cloud metadata endpoints, overwrite LLM provider configuration and API keys with attacker-controlled values, or initiate OAuth device-code flows to obtain persistent access tokens stored in auth.json.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Affected products
nesquena · hermes-webuiRelated CVEs — nesquena hermes-webui
In the same product, most dangerous first.
CVE-2026-58123CRITICALHermes WebUI < 0.51.788 Unauthenticated RCE via Terminal APIEPSS 4.6%CVE-2026-49959HIGHHermes WebUI < 0.51.311 RCE via Git Configuration InjectionEPSS 0.9%CVE-2026-49955MEDIUMHermes WebUI < 0.51.270 Resource Exhaustion via passkey/optionsEPSS 0.6%CVE-2026-49973CRITICALHermes WebUI < 0.51.358 Unauthenticated Password Takeover via /api/settingsEPSS 0.5%CVE-2026-55205MEDIUMHermes WebUI < 0.51.468 - Resource Exhaustion via Unauthenticated OAuth Flow EndpointEPSS 0.5%CVE-2026-6832HIGHNesquena Hermes WebUI Arbitrary File Deletion via Unvalidated session_idEPSS 0.5%
References
https://github.com/nesquena/hermes-webui/commit/70596e6993be0d4cee083c1c1a86f5e7ad5d57b7https://github.com/nesquena/hermes-webui/pull/3758https://github.com/nesquena/hermes-webui/releases/tag/v0.51.307https://www.vulncheck.com/advisories/hermes-webui-authentication-bypass-via-x-forwarded-for-header-spoofing