CVE-2026-55205
Hermes WebUI < 0.51.468 - Resource Exhaustion via Unauthenticated OAuth Flow Endpoint
CVSS Score
5.3
EPSS Score
0.0%
EPSS Percentile
0th
Hermes WebUI before 0.51.468 contains a resource exhaustion vulnerability in the unauthenticated POST /api/onboarding/oauth/start endpoint that allows unbounded accumulation of in-memory flow state and daemon threads. Attackers can send repeated or concurrent requests to exhaust server memory and thread resources, potentially triggering repeated outbound device-code requests to upstream OAuth providers.
| CWE | CWE-770 |
| Vendor | nesquena |
| Product | hermes-webui |
| Published | Jun 18, 2026 |
| Last Updated | Jun 18, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Affected Versions
nesquena / hermes-webui
0 < 0.51.468
References
github.com: https://github.com/nesquena/hermes-webui/releases/tag/v0.51.468 github.com: https://github.com/nesquena/hermes-webui/pull/3970 github.com: https://github.com/nesquena/hermes-webui/pull/4338 github.com: https://github.com/nesquena/hermes-webui/commit/ce272d9cd5f8e5a4521278f56eb5388010901646 vulncheck.com: https://www.vulncheck.com/advisories/hermes-webui-resource-exhaustion-via-unauthenticated-oauth-flow-endpoint
Credits
Chia Min Jun Lennon