Apache HttpClient: SCRAM-SHA-256 mutual authentication bypass may cause the client to accept authentication without proper mutual authentication verification
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.3epss 0.5%
exploitation probability
0.5%top 63% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Affected products
Apache Software Foundation · Apache HttpClientReferences
https://access.redhat.com/security/cve/CVE-2026-40542https://bugzilla.redhat.com/show_bug.cgi?id=2460518https://lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40542.jsonhttp://www.openwall.com/lists/oss-security/2026/04/22/5