CVE-2026-40542NVD

Vulnerability Summary

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.

Severity Level

HIGH(7.3)

Published Date

Apr 22, 2026

Last Modified

Sep 9, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.70%Probability

Root Weakness (CWE)

CWE-304: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CWE-325: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics — Score 7.3 (HIGH)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityLow

IntegrityLow

AvailabilityLow

Affected & Patched Versions

Affected Versions

Apache Httpclient

Patched Versions

Not provided by NVD for this CVE.

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