CVE-2020-21548: Saitoha Libsixel

High severity, CVSS 8.8. EPSS: 1.1% chance of exploitation in the next 30 days.

Libsixel 1.8.3 contains a heap-based buffer overflow in the sixel_encode_highcolor function in tosixel.c.

Affected products

• Saitoha Libsixel: version 1.8.3 only

Published 2021-09-17. Last modified 2026-06-17.