CVE-2021-40656: Libsixel

High severity, CVSS 8.8. EPSS: 1% chance of exploitation in the next 30 days.

libsixel before 1.10 is vulnerable to Buffer Overflow in libsixel/src/quant.c:867.

Affected products

• Libsixel Libsixel: before 1.10.0 (fixed in 1.10.0)

Published 2022-04-08. Last modified 2026-06-17.