CVE-2021-45958: Debian Linux

Medium severity, CVSS 5.5. EPSS: 1.6% chance of exploitation in the next 30 days.

UltraJSON (aka ujson) through 5.1.0 has a stack-based buffer overflow in Buffer_AppendIndentUnchecked (called from encode). Exploitation can, for example, use a large amount of indentation.

Affected products

• Debian Debian Linux: version 9.0 only
• Fedoraproject Fedora: version 35 only; version 36 only; version 37 only
• Ultrajson Project Ultrajson: before 5.2.0 (fixed in 5.2.0)

Published 2022-01-01. Last modified 2026-06-17.