NULL Pointer Dereference Affecting libsixel package, versions *


Severity

Recommended
0.0
low
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
0.13% (2nd percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-ECHOLATEST-LIBSIXEL-21184815
  • published18 Oct 2026
  • disclosed14 May 2026

Introduced: 14 May 2026

CVE-2026-44638  (opens in a new tab)
CWE-476  (opens in a new tab)

How to fix?

There is no fixed version for Echo:latest libsixel.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libsixel package and not the libsixel package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. From to 1.8.7-r1, a wrong NULL check after an allocation call in sixel_decode_raw and sixel_decode causes a NULL pointer dereference whenever the allocation fails. The check tests the address of the output parameter (always non-NULL) instead of the value the malloc returned. On allocation failure, the function continues and writes through a NULL pointer, crashing the process. This is a denial of service against any caller of these public APIs that hits a low-memory condition. This vulnerability is fixed in 1.8.7-r2.

CVSS Base Scores

version 3.1