🛡️ CVE-2026-42255 — dnsserver

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 changed, meaning a successful attack can affect components beyond the vulnerable one. Rated impact: confidentiality none, 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:C/C:N/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: Changed — a successful attack reaches components beyond the vulnerable one.
• Confidentiality impact: None.
• 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-2026-42255 is classified as CWE-684: Incorrect Provision of Specified Functionality. The code does not function according to its published specifications, potentially leading to incorrect usage.

Affected software

CVE-2026-42255 is recorded against 1 package.

• dnsserver (fixed in 15.0)

Timeline and source

Published on 26 April 2026 and last revised on 17 June 2026. No public exploit is currently recorded for this entry. Record sourced from NVD.

References

github.com

Other advisories for this package

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

• CVE-2025-50334 (7.5 High, published 8 Jan 2026)
• CVE-2024-56089 (7.5 High, published 1 Dec 2025)
• CVE-2024-56946 (5.3 Medium, published 3 Feb 2025)
• CVE-2023-28457 (7.5 High, published 18 Sep 2024)
• CVE-2023-28456 (7.5 High, published 18 Sep 2024)
• CVE-2023-28455 (7.5 High, published 18 Sep 2024)
• CVE-2023-49203 (7.5 High, published 18 Sep 2024)
• CVE-2023-28451 (7.5 High, published 18 Sep 2024)

Same weakness in other software

These advisories are the same class of weakness (CWE-684: Incorrect Provision of Specified Functionality) in other software:

• CVE-2026-52735 (9.5 Critical, published 18 Aug 2026)
• CVE-2026-35381 (2.0 Low, published 6 Jul 2026)
• CVE-2026-44597 (3.7 Low, published 7 May 2026)
• CVE-2026-40685 (6.5 Medium, published 30 Apr 2026)
• CVE-2026-40684 (5.9 Medium, published 30 Apr 2026)
• CVE-2026-35379 (2.0 Low, published 22 Apr 2026)
• CVE-2025-66384 (8.2 High, published 28 Nov 2025)
• CVE-2025-55174 (3.2 Low, published 26 Nov 2025)

Details

Affected Packages

References