Skip to content
Fencer Vulns
high 7.5

CVE-2021-32762 json

Integer overflow that can lead to heap overflow in redis-cli, redis-sentinel on some platforms

published 2021-10-04 5 y ago modified 2026-09-08 2 mo ago also BIT-keydb-2021-32762 , BIT-redis-2021-32762 , BIT-valkey-2021-32762 , EUVD-2021-19530 , GHSA-833w-8v3m-8wwr

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
2.6%
EPSS 2.6% chance of exploitation in 30 days, percentile 85%
public exploits
0
none known

Summary

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.

Patch / fix

  • bitnami keydb 5.0.14, 6.0.16, 6.2.6
  • bitnami redis 5.0.14, 6.0.16, 6.2.6
  • bitnami valkey 5.0.14, 6.0.16, 6.2.6
  • redis redis 5.0.14, 6.0.16, 6.2.6
  • redis Debian 14, Debian 13, Debian 12 5:6.0.16-1

debian advisories DEBIAN-CVE-2021-32762

  • redis SLE Module for Server Applications 15 SP3, SLE Module for Server Applications 15 SP2 6.0.14-6.8.1

suse advisories SUSE-SU-2021:3772-1

  • redis openSUSE Tumbleweed 6.2.6-1.1
  • redis openSUSE Leap 15.3 6.0.14-6.8.1

opensuse advisories openSUSE-SU-2024:11563-1openSUSE-SU-2021:3772-1

  • redis Alpine 3.12, Alpine 3.11 5.0.14-r0
  • redis Alpine 3.13 6.0.16-r0
  • redis Alpine 3.24, Alpine 3.23, Alpine 3.22 +8 more 6.2.6-r0

alpine advisories ALPINE-CVE-2021-32762

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • redis CBL-Mariner 2.0 6.2.6-1

azure linux advisories AZL-6851

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-32762 updated cvss 7.5

redis: Integer overflow in redis-cli, redis-sentinel on some platforms

  • Red Hat OpenStack Platform 10 (Newton) redis Red Hat OpenStack Platform 13 (Queens) redis
    affected: no fix planned “Out of support scope”
  • Red Hat 3scale API Management Platform 2 redis Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/redisgraph-tls-rhel8 Red Hat Ansible Automation Platform 1.2 redis Red Hat Ansible Tower 3 redis Red Hat Enterprise Linux 8 redis Red Hat Enterprise Linux 9 redis
    +1 more products
    Red Hat Software Collections rh-redis5-redis, rh-redis6-redis
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.58% chance of exploitation in the next 30 days, higher than 85% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 9.0 AV:N/AC:L/Au:S/C:C/I:C/A:C
OSV 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
bitnami keydb
>=5.0.0, <5.0.14
>=6.0.0, <6.0.16
>=6.2.0, <6.2.6
5.0.14
6.0.16
6.2.6
bitnami redis
>=5.0.0, <5.0.14
>=6.0.0, <6.0.16
>=6.2.0, <6.2.6
5.0.14
6.0.16
6.2.6
bitnami valkey
>=5.0.0, <5.0.14
>=6.0.0, <6.0.16
>=6.2.0, <6.2.6
5.0.14
6.0.16
6.2.6

Affected products

  • redis redis

Classification

Weakness
  • CWE-190 Integer Overflow or Wraparound
  • CWE-680 Integer Overflow to Buffer Overflow
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

The maintainers of redis/redis published their own advisory on GitHub. Reviewed sources take precedence over it.