Description
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.
Affected products
apache: httpclient
References10
- lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97 Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/04/22/5 Mailing ListThird Party Advisory
- access.redhat.com/errata/RHSA-2026:60239
- access.redhat.com/errata/RHSA-2026:60246
- access.redhat.com/errata/RHSA-2026:60247
- access.redhat.com/errata/RHSA-2026:60248
- access.redhat.com/errata/RHSA-2026:60249
- access.redhat.com/errata/RHSA-2026:60250
- access.redhat.com/errata/RHSA-2026:60251
- access.redhat.com/errata/RHSA-2026:60252
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - EPSS — exploit probability
- 1% percentile: 46 · as of 13 November 2026
- CWE
- CWE-304CWE-325
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