CVE-2026-18938

Publication date 7 August 2026

Last updated 27 August 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

6.2 · Medium

Score breakdown

Description

A flaw was found in p11-kit. A local attacker, or one with equivalent access to a reachable RPC channel, could exploit an integer overflow vulnerability. By sending specially crafted messages, the attacker can cause the system to miscalculate memory allocation for nested attributes. This leads to a memory corruption issue, specifically a heap out-of-bounds write, which can crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). This vulnerability is only exploitable on 32 bit systems.

Status

Package Ubuntu Release Status
p11-kit 26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Fixed 0.25.3-4ubuntu2.2
22.04 LTS jammy
Fixed 0.24.0-6ubuntu0.1
20.04 LTS focal
Fixed 0.23.20-1ubuntu0.1+esm1
18.04 LTS bionic
Fixed 0.23.9-2ubuntu0.1+esm1
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
p11-kit

Severity score breakdown

CVSS version: CVSS v3.0

Base score 6.2 · Medium

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-8687-1
    • p11-kit vulnerabilities
    • 27 August 2026

Other references

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