Ubuntu update for gnupg2

1) Input validation error

EUVDB-ID: #VU106992

Risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-30258

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to disable signature verification.

The vulnerability exists due to an error when handling subkey data. A remote attacker can trick the victim into importing a specially crafted certificate with subkey data that lacks a valid backsig or that has incorrect usage flags and disable signature verification for other signing keys.

Mitigation

Update the affected package gnupg2 to the latest version.

Vulnerable software versions

Ubuntu: 20.04 - 24.10

gpg (Ubuntu package): before 2.2.19-3ubuntu2.4

gnupg2 (Ubuntu package): before 2.2.19-3ubuntu2.4

gnupg (Ubuntu package): before 2.2.19-3ubuntu2.4

CPE2.3

• cpe:2.3:o:canonical:ubuntu:20.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:22.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:24.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:24.10:*:*:*:*:*:*:*
• cpe:2.3:a:canonical:gpg_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:gnupg2_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:gnupg_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://ubuntu.com/security/notices/USN-7412-1

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.