CVE-2026-49955mediumCWE-770

CVE-2026-49955: medium-severity vulnerability in nesquena hermes-webui

Hermes WebUI < 0.51.270 Resource Exhaustion via passkey/options

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.9epss 0.6%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Affected products
nesquena · hermes-webui
Related CVEs — nesquena hermes-webui

In the same product, most dangerous first.

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