CVE-2026-32259
Description
A flaw was found in ImageMagick. Processing a specially crafted file with the sixel encoder can cause a stack-based buffer overflow when a memory allocation fails, leading to a denial of service.
Statement
To exploit this issue, an attacker needs to convince a user to process a specially crafted file that makes ImageMagick use the sixel encoder. Furthermore, this flaw is only triggered when a memory allocation fails, limiting the possibility of exploitation even further.
Default Red Hat Enterprise Linux security features, including SELinux enforcement, Address Space Layout Randomization (ASLR) and NX (No-Execute) stack protection, significantly increase the difficulty of achieving arbitrary code execution, limiting the impact of this vulnerability to a denial of service.
Due to these reasons, this vulnerability has been rated with a moderate severity.
Mitigation
To mitigate this vulnerability, disable the vulnerable encoder by adding the following line to the ImageMagick policy.xml file, typically located in the directory /etc/ImageMagick-7/, /etc/ImageMagick-6/ or /etc/ImageMagick/:
<policy domain="coder" rights="none" pattern="sixel" />
To reduce the risk of exploitation, avoid processing sixel files from untrusted sources. If ImageMagick is deployed in a way that it processes files from untrusted sources automatically, consider running the application inside a container or a restricted sandbox environment to limit the potential security impact.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.3 | N/A | 6.7 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | High |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | Low | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:H
cve.org: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)
Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.
Integrity,Confidentiality,Availability,Access Control
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism
Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy.
Integrity,Confidentiality,Availability,Access Control,Other
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other
When the consequence is arbitrary code execution, this can often be used to subvert any other security service.
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