CVE-2026-40542
Medium
Elevated severity or exploit probability.
CVSS base
7.3
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
EPSS — probability of exploitation (30 days)
0.6%
45.2th percentile
CISA KEV
Not listed
Weakness / dates
CWE-325
Published 2026-04-22 · modified 2026-09-09
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | L | Low |
| Integrity | L | Low |
| Availability | L | Low |
Timeline
- 2026-04-22 — Published (NVD)
- 2026-09-09 — Last modified (NVD)
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
References
- https://lists.apache.org/thread/tfmgv86xr0z1y096vs3z0y315t1v3o97
- http://www.openwall.com/lists/oss-security/2026/04/22/5
- 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
- https://access.redhat.com/errata/RHSA-2026:60254
- https://access.redhat.com/errata/RHSA-2026:60256
- https://access.redhat.com/errata/RHSA-2026:60259
- https://access.redhat.com/security/cve/CVE-2026-40542
- https://bugzilla.redhat.com/show_bug.cgi?id=2460518
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40542.json