drm/amd/display: Fix divide-by-zero in calculate_mcache_setting on zero viewport
CVE-2026-74449 · published 15 Aug 2026
How serious is it
- Severity: high, CVSS score 7.8 out of 10.
- No exploit prediction (EPSS) score yet.
- Not on the CISA list of exploited vulnerabilities.
- No public exploit in Exploit-DB.
Is your app affected by CVE-2026-74449?
Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.
Who is affected
- Linux Linux: 70839da6360500a82e4d5f78499284474cbed7c1 to < 70f5f4ddba0d2d89e77ec13b79cdcfbef33be0d9, 70839da6360500a82e4d5f78499284474cbed7c1 to < 23a541c31b45fa813b33269376f6bd53535429a8, 70839da6360500a82e4d5f78499284474cbed7c1 to < 1f93537881fd22712732a60ad12572a3fd40c0ec, 70839da6360500a82e4d5f78499284474cbed7c1 to < f327e389c07cfc3a2f6ff54f6214e1a52d457edc
- Linux Linux: 6.11
How to check
- Find out whether you run the affected product and which version, then compare it with the versions above.
How to fix
Copies a prompt for Claude Code, Cursor or Codex that asks it to check whether you run this product.
- Apply the vendor's update or mitigation from the references below. If there is none yet, limit exposure of the affected service until there is.
- If a vulnerable version was live, check your logs and rotate the secrets that server could read.
The advisory
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Fix divide-by-zero in calculate_mcache_setting on zero viewport
If a plane reaches calculate_mcache_setting with a zero-area viewport,
calculate_mcache_setting exits early with num_mcaches == 0 and
mvmpg_width/height == 0. This will cause a divide-by-zero panic and can
also cause an underflow on num_mcaches.
Fix this by changing calculate_mcache_setting to bool and adding guards
after each calculate_mcache_row_bytes call. If num_mcaches or
mvmpg_width/height is zero, return a false. Callers will propagate the
failure as a rejected mode, which prevents the panic.
(cherry picked from commit 29c0f7c655f47bcbd575ff75e58480df6ec3c9da)
Check your whole app
Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.
References
- git.kernel.org/stable/c/70f5f4ddba0d2d89e77ec13b79cdcfbef33be0d9
- git.kernel.org/stable/c/23a541c31b45fa813b33269376f6bd53535429a8
- git.kernel.org/stable/c/1f93537881fd22712732a60ad12572a3fd40c0ec
- git.kernel.org/stable/c/f327e389c07cfc3a2f6ff54f6214e1a52d457edc
Merged from CVE List. Last updated 25 Oct 2026. All vulnerabilities · RSS · JSON