CVE-2021-32762: Debian Linux

High severity, CVSS 8.8. EPSS: 2.6% chance of exploitation in the next 30 days.

Redis is an open source, in-memory database that persists on disk. The redis-cli command line tool and redis-sentinel service may be vulnerable to integer overflow when parsing specially crafted large multi-bulk network replies. This is a result of a vulnerability in the underlying hiredis library which does not perform an overflow check before calling the calloc() heap allocation function. This issue only impacts systems with heap allocators that do not perform their own overflow checks. Most modern systems do and are therefore not likely to be affected. Furthermore, by default redis-sentinel uses the jemalloc allocator which is also not vulnerable. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14.

Affected products

• Debian Debian Linux: version 10.0 only; version 11.0 only
• Fedoraproject Fedora: version 33 only; version 34 only; version 35 only
• Netapp Management Services For Element Software: affected versions not specified
• Netapp Management Services For Netapp Hci: affected versions not specified
• Oracle Communications Operations Monitor: version 4.3 only; version 4.4 only; version 5.0 only
• Redis Redis: from 5.0.0, before 5.0.14 (fixed in 5.0.14); from 6.0.0, before 6.0.16 (fixed in 6.0.16); from 6.2.0, before 6.2.6 (fixed in 6.2.6)

Published 2021-10-04. Last modified 2026-06-17.