cacalabs libcaca up to 0.99.beta20 File heap-based overflow

Summaryinfo

A vulnerability, which was classified as critical, has been found in cacalabs libcaca up to 0.99.beta20. This affects an unknown part of the component File Handler. This manipulation causes heap-based overflow. This vulnerability is handled as CVE-2026-42046. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in cacalabs libcaca up to 0.99.beta20. Affected by this vulnerability is an unknown functionality of the component File Handler. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

libcaca is a colour ASCII art library. In 0.99.beta20 and earlier, an integer overflow vulnerability in libcaca's canvas import functionality allows an attacker to cause a controlled heap out-of-bounds write (heap overflow) by supplying a crafted file in the "caca" format. Depending on the build configuration and memory allocator, this may lead to memory corruption or remote code execution. This is the same vulnerability as CVE-2021-3410 but the fix at that time was not fully correct. Commit fb77acff9ba6bb01d53940da34fb10f20b156a23 fixes this vulnerability.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-42046 since 04/23/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 316866 (Fedora 45 : libcaca (2026-1151ae6bdf)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability. Applying the patch fb77acff9ba6bb01d53940da34fb10f20b156a23 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (316866). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• cacalabs

Name

• libcaca

Version

• 0.99.beta20

License

• open-source

Website

• Product: https://github.com/cacalabs/libcaca/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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