What’s Vulnerable › Vulnerabilities

CVE-2021-32627: Integer overflow issue with Streams in Redis

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-10-04 · updated 2026-06-17
• Weakness: CWE-190

Description

Redis is an open source, in-memory database that persists on disk. In affected versions an integer overflow bug in Redis can be exploited to corrupt the heap and potentially result with remote code execution. The vulnerability involves changing the default proto-max-bulk-len and client-query-buffer-limit configuration parameters to very large values and constructing specially crafted very large stream elements. The problem is fixed in Redis 6.2.6, 6.0.16 and 5.0.14. For users unable to upgrade an additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the proto-max-bulk-len configuration parameter. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.

Affected products

• Debian Linux: 10.0, 11.0
• Fedoraproject Fedora: 33, 34, 35
• NetApp Management Services For Element Software: all versions
• NetApp Management Services For Netapp Hci: all versions
• Oracle Corporation Communications Operations Monitor: 4.3, 4.4, 5.0
• Redis: from 5.0.0 before 5.0.14; from 6.0.0 before 6.0.16; from 6.2.0 before 6.2.6 — fixed in 5.0.14, 6.0.16, 6.2.6

How to fix

Upgrade to a fixed version: Redis 5.0.14, 6.0.16, 6.2.6. Check the vendor advisory for mitigations.

References

• https://github.com/redis/redis/commit/f6a40570fa63d5afdd596c78083d754081d80ae3
• https://github.com/redis/redis/security/advisories/GHSA-f434-69fm-g45v
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HTYQ5ZF37HNGTZWVNJD3VXP7I6MEEF42/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VL5KXFN3ATM7IIM7Q4O4PWTSRGZ5744Z/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WR5WKJWXD4D6S3DJCZ56V74ESLTDQRAB/
• https://security.gentoo.org/glsa/202209-17
• https://security.netapp.com/advisory/ntap-20211104-0003/
• https://www.debian.org/security/2021/dsa-5001
• https://www.oracle.com/security-alerts/cpuapr2022.html
• https://github.com/redis/redis/commit/f6a40570fa63d5afdd596c78083d754081d80ae3
• https://github.com/redis/redis/security/advisories/GHSA-f434-69fm-g45v
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HTYQ5ZF37HNGTZWVNJD3VXP7I6MEEF42/

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