CVE-2026-74443
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
In the Linux kernel, the vmwgfx driver has a vulnerability where the DMA command body size is not checked against the suffix pointer. This can cause the suffix pointer to underflow and overwrite verified fields of a previous command, enabling a TOCTOU attack. The fix rejects the command if the body is too small.
Risk Assessment
A local attacker could modify verified fields of other commands, potentially leading to unauthorized GPU operations or privilege escalation.
Recommendation
Apply the Linux kernel update containing the fix (commit from the vmwgfx series).
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: bound DMA command body size against suffix pointer vmw_cmd_dma() locates the DMA suffix at (unsigned long) &cmd->body + header->size - sizeof(*suffix) without checking that header->size is large enough to contain both cmd->body and the suffix. An undersized header makes the suffix pointer underflow back into the previous command in the bounce buffer. The verifier later writes suffix->maximumOffset, clobbering verified fields of an already-relocated earlier command -- a TOCTOU on the device-visible command stream that lets one command rewrite another's GMR id, surface id, or other authenticated fields. Reject the command if the body is too small for the suffix to fit.