🛡️ CVE-2026-40542 — httpclient

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality low, integrity low, availability low.

CVSS metrics in full

The score comes from this vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

• Attack vector: Network — reachable from anywhere that can route to the service.
• Attack complexity: Low — the attack works reliably, with no preparation.
• Privileges required: None — an unauthenticated stranger can try it.
• User interaction: None — nobody has to be tricked into anything.
• Scope: Unchanged — the damage stays inside the vulnerable component.
• Confidentiality impact: Low — limited, and the attacker does not choose what is affected.
• Integrity impact: Low — limited, and the attacker does not choose what is affected.
• Availability impact: Low — limited, and the attacker does not choose what is affected.

Weakness class

CVE-2026-40542 is classified as CWE-304: Missing Critical Step in Authentication. The product implements an authentication technique, but it skips a step that weakens the technique.

Affected software

CVE-2026-40542 is recorded against 2 packages.

• httpclient
• org.apache.httpcomponents.client5:httpclient5 (from 5.6-alpha1 up to 5.6.1)

Timeline and source

Published on 22 April 2026 and last revised on 15 July 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

lists.apache.org
www.openwall.com
access.redhat.com
bugzilla.redhat.com
security.access.redhat.com

Other advisories for this package

httpclient has other advisories on record. If you are patching this one, these are worth checking on the same host:

• CVE-2026-64607 (5.3 Medium, published 31 Jul 2026)
• CVE-2025-27820 (7.5 High, published 24 Apr 2025)
• CVE-2024-50342 (3.1 Low, published 6 Nov 2024)
• RHSA-2013:0839 (published 29 Sep 2024)
• RHSA-2013:0834 (published 29 Sep 2024)
• RHSA-2015:1592 (published 13 Sep 2024)

Same weakness in other software

These advisories are the same class of weakness (CWE-304: Missing Critical Step in Authentication) in other software:

• CVE-2026-61466 (9.1 Critical, published 6 Aug 2026)
• CVE-2026-67351 (8.8 High, published 30 Jul 2026)
• CVE-2026-55957 (8.0 High, published 6 Jul 2026)
• CVE-2026-57915 (7.3 High, published 26 Jun 2026)
• CVE-2026-42452 (8.1 High, published 8 May 2026)
• CVE-2025-43798 (6.5 Medium, published 15 Sep 2025)
• CVE-2025-24322 (8.1 High, published 20 Aug 2025)
• CVE-2025-55138 (7.4 High, published 7 Aug 2025)

CVE-2026-40542 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Affected Packages

References