What is CVE-2026-33023?

CVE-2026-33023 is a high-severity vulnerability in Saitoha Libsixel, classified under Use After Free. CVSS score: 7.8/10. Published 2026-04-14.

How severe is CVE-2026-33023?

High severity. CVSS v3 base score is 7.8 out of 10.

Use After Free in Saitoha Libsixel

CVE-2026-33023

libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. In versions 1.8.7 and prior, when built with the --with-gdk-pixbuf2 option, a use-after-free vulnerability exists in load_with_gdkpixbuf() in loader.c. The clea…

Vulnerability class: Use-After-Free

EPSS: 0.000 (0.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Saitoha Libsixel — versions < 1.8.7-r1

Weakness classification (CWE)

CWE-416 — Use After Free

References

https://github.com/saitoha/libsixel/security/advisories/GHSA-hr25-g2j6-qjw6 (x_refsource_CONFIRM)
https://github.com/saitoha/libsixel/releases/tag/v1.8.7-r1 (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-33023?: CVE-2026-33023 is a high-severity vulnerability in Saitoha Libsixel, classified under Use After Free. CVSS score: 7.8/10. Published 2026-04-14.
How severe is CVE-2026-33023?: High severity. CVSS v3 base score is 7.8 out of 10.