SECURELYN

CVE-2026-104056

Authlib version 1.7.2 and below contains a vulnerability where discovery JSON metadata is cached without validation or issuer-origin binding. This allows a poisoned discovery response to replace all endpoint values with attacker-controlled values rather than endpoint URLs that share the origin of the configured server metadata URL.

Scores

9.8
CVSS 9.8 out of 10, critical severity.
0.2%
EPSS 0.2% chance of exploitation in the next 30 days.

The facts

Published
1 October 2026
Last changed
5 October 2026
NVD status
Awaiting Analysis
Severity
Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.2% chance of exploitation activity in the next 30 days (percentile 6).

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References