High 7.3Published Apr 22, 2026

CVE-2026-40542Apache HttpClient: SCRAM-SHA-256 mutual authentication bypass may cause the client to accept authentication without proper mutual authentication verification

Updated under an hour ago (Oct 27, 2026, 8:30 AM ET)

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It affects Apache Software Foundation Apache HttpClient and 31 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Apache Software Foundation Apache HttpClient

Exploited in the last 30 days

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: 7.3 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Weakness (CWE): CWE-304, CWE-325
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: apache
NVD analysis: Modified
Record last updated: Sep 9, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Apache Software Foundation Apache HttpClient apache_software_foundation:apache_httpclient (from the name)	from 5.6 before 5.6.1	CNA record
Red Hat OpenShift Developer Tools and Services 4.12 redhat:ocp_tools	from 1786628667 not affected	CISA ADP
Red Hat Cryostat 4 redhat:cryostat	4	CISA ADP
Red Hat Migration Toolkit for Applications 8 redhat:migration_toolkit_applications	8	CISA ADP
Red Hat OpenShift Serverless redhat:serverless	1	CISA ADP
Red Hat Red Hat AMQ Broker 7 redhat:amq_broker	7	CISA ADP
Red Hat Red Hat AMQ Clients redhat:amq_clients	2023	CISA ADP
Red Hat Red Hat build of Apache Camel 4 for Quarkus 3 redhat:camel_quarkus	3	CISA ADP
Red Hat Red Hat build of Apache Camel for Spring Boot 4 redhat:camel_spring_boot	4	CISA ADP
Red Hat Red Hat build of Apache Camel - HawtIO 4 redhat:apache_camel_hawtio	4	CISA ADP
1–10 of 32

References

References

https://lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97	vendor-advisory, mailing-list
http://www.openwall.com/lists/oss-security/2026/04/22/5	mailing-list, third-party-advisory
https://access.redhat.com/errata/RHSA-2026:60239
https://access.redhat.com/errata/RHSA-2026:60246
https://access.redhat.com/errata/RHSA-2026:60247
https://access.redhat.com/errata/RHSA-2026:60248
https://access.redhat.com/errata/RHSA-2026:60249
https://access.redhat.com/errata/RHSA-2026:60250
https://access.redhat.com/errata/RHSA-2026:60251
https://access.redhat.com/errata/RHSA-2026:60252
1–10 of 16

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.