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CVE-2026-40542

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

Published: Apr 22, 2026Updated: Jun 30, 2026 Sources: CVE List NVDCWE-304
7.3HIGH
NVD MITRE
EPSS Score
0.5%
Top 63.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:LI:LA:L
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:LIntegrity
Low
A:LAvailability
Low
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Weaknesses

CWE-304CWE-325

Affected Products

Apache Software Foundation
oss-project·USaka apache foundation
Apache HttpClientLibraryLibrary
OSS Libraries / generic-library
apache
oss-project·USaka apache http server, apache httpd
httpclientLibrary
OSS Libraries / generic-library

Exploitability

Official Patch Available
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References

https://lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97
lists.apache.org
http://www.openwall.com/lists/oss-security/2026/04/22/5
openwall.com
https://access.redhat.com/security/cve/CVE-2026-40542
access.redhat.com
and 2 more references View all →
News mentions
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