CVE-2026-40542
Missing critical step in authentication in Apache HttpClient 5.6 allows an attacker to cause the client to accept SCRAM-SHA-256 authentication without proper mutual authentication verification. Users are recommended to upgrade to version 5.6.1, which fixes this issue.
Scoring
- Severity
- HIGH
- CVSS base score
- 7.3
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- EPSS probability
- 0.56%
- CWE
- CWE-304
- Published
- 2026-04-22
- Last modified
- 2026-09-09
Affected products
- Apache Software Foundation Apache HttpClient
Weakness type
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