CVE-2026-40542CWE-304CWE-325

CVE-2026-40542

High · published April 22, 2026

CVSS v3.1
7.3
EPSS
1%
Percentile
52.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.3 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CVSS v4.0
Not supplied
EPSS
0.00702 · 52.7th percentile
Weaknesses
CWE-304 · Missing Critical Step in Authentication; CWE-325 · Missing Cryptographic Step
Published
2026-04-22T12:16Z
Affected products (1)
ProductVersionsFixed in
apache/httpclientall versions—
References (16)
https://lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97 · [email protected]http://www.openwall.com/lists/oss-security/2026/04/22/5 · af854a3a-2127-422b-91ae-364da2661108https://access.redhat.com/errata/RHSA-2026:60239 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60246 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60247 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60248 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60249 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60250 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60251 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60252 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60254 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60256 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:60259 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/security/cve/CVE-2026-40542 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://bugzilla.redhat.com/show_bug.cgi?id=2460518 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40542.json · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
EPSS history
Timeline
  • 22 APR 07:07Z
    Apache HttpClient: SCRAM-SHA-256 mutual authentication bypass may cause the client to accept authentication without proper mutual authentication verification
    cvelistv5