CVE-2025-66621

Apache James: SASL OAUTHBEARER do not validate aud in JWT payload if misconfigred

Published Nov 6, 2026 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
Description
Apache James SASL OAuthBearer/XOAUTH2 prior versions 3.9.1 fails to validate correctly AUD claim of JWT payloads when introspection is not configured.

This allows an attacker with valid credentials to access the mail server even if they are not authorized to do so.

We recommend users to upgrade to non vulnerable version that forces explicit configuration of aud claims and forces introspection.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Apache
Apache james
Vendors & Products Apache
Apache james
Type Values Removed Values Added
Description Apache James SASL OAuthBearer/XOAUTH2 prior versions 3.9.1 fails to validate correctly AUD claim of JWT payloads when introspection is not configured. This allows an attacker with valid credentials to access the mail server even if they are not authorized to do so. We recommend users to upgrade to non vulnerable version that forces explicit configuration of aud claims and forces introspection.
Title Apache James: SASL OAUTHBEARER do not validate aud in JWT payload if misconfigred
Weaknesses CWE-345
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
apache
Published
Updated
Nov 10, 2026, 6:52 PM
Reserved
Dec 5, 2025, 3:03 PM
Status
Deferred
Published
Nov 6, 2026, 12:17 PM
Modified
Nov 10, 2026, 7:17 PM