CVE-2026-49955

Medium

Description

Hermes WebUI before version 0.51.270 contains a resource exhaustion vulnerability that allows unauthenticated remote attackers to degrade service availability by repeatedly calling the passkey options endpoint without completing assertion. Attackers can send unlimited POST requests to the authentication endpoint, causing unbounded growth of the challenge store file and excessive CPU and disk I/O through repeated JSON file rewrites.

SeverityMedium

CVSS5.3

Exploit probability—

ProductNesquena Hermes-webui

PublishedJun 9, 2026

First seenJun 9, 2026

Weakness typeCWE-770Allocation of resources without limits

How to fix

Update

nesquena hermes-webui0.51.270 or later

Patches

github.com/nesquena/hermes-webui/commit/58528a4d88b0fa4f7b822e31d6051c669769bd3b

Vendor advisories

github.com/nesquena/hermes-webui/releases/tag/v0.51.270

Affected products

Product	Affected versions	Fixed in
nesquena hermes-webui	v < 0.51.270	0.51.270

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