CVE-2026-55205

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/nesquena/hermes-webui/commit/ce272d9cd5f8e5a4521278f56eb5388010901646
https://github.com/nesquena/hermes-webui/pull/3970
https://github.com/nesquena/hermes-webui/pull/4338
https://github.com/nesquena/hermes-webui/releases/tag/v0.51.468
https://www.vulncheck.com/advisories/hermes-webui-resource-exhaustion-via-unauthenticated-oauth-flow-endpoint
https://github.com/nesquena/hermes-webui/pull/3970

Configurations

No configuration.

History

18 Jun 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-18 17:16

Updated : 2026-06-22 18:43

NVD link : CVE-2026-55205

Mitre link : CVE-2026-55205

CVE.ORG link : CVE-2026-55205

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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