What is CVE-2026-55205?

CVE-2026-55205 is a medium-severity vulnerability in Nesquena Hermes-webui, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-06-18.

How severe is CVE-2026-55205?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Resource exhaustion in Nesquena Hermes-webui

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 re…

EPSS: 0.005 (41.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Nesquena Hermes-webui — versions 0, 0.51.468

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

Release Notes (release-notes)
Researcher Pull Request (issue-tracking, technical-description)
Maintainer Pull Request (issue-tracking)
Patch Commit (patch)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-55205?: CVE-2026-55205 is a medium-severity vulnerability in Nesquena Hermes-webui, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-06-18.
How severe is CVE-2026-55205?: Medium severity. CVSS v3 base score is 5.3 out of 10.