CVE-2026-32249

Description

A flaw was found in Vim. A NULL pointer dereference can occur when the NFA regex compiler processes a specific character collection, more specifically one that contains a combining character acting as the endpoint of a character range (e.g., [0-0\u05bb]). A process or user that can supply a regex pattern can cause an application crash, resulting in a denial of service.

Statement

To exploit this issue, an attacker needs to be able to supply a malicious regex pattern to be processed by the NFA regex compiler, including via plugins or command line arguments. Also, this flaw can cause an application crash, resulting only in a denial of service with no other security impact. Due to these reasons, this vulnerability has been rated with low severity.

Mitigation

To mitigate this vulnerability, disable the NFA (Non-deterministic Finite Automaton) regex engine and enable the traditional backtracking engine by adding the following option to the Vim configuration file:

set regexpengine=1

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.55.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredNoneNoneN/A
User InteractionRequiredRequiredN/A
ScopeUnchangedUnchangedN/A
ConfidentialityNoneNoneN/A
Integrity ImpactNoneNoneN/A
Availability ImpactHighHighN/A

Vector

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

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

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart

NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.

Integrity,Confidentiality

Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory

In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.

Frequently Asked Questions

Want to get errata notifications? Sign up here.