What’s Vulnerable › Vulnerabilities

CVE-2025-40193: xtensa: simdisk: add input size check in proc_write_simdisk

• Severity: unknown
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-11-12 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: xtensa: simdisk: add input size check in proc_write_simdisk A malicious user could pass an arbitrarily bad value to memdup_user_nul(), potentially causing kernel crash. This follows the same pattern as commit ee76746387f6 ("netdevsim: prevent bad user input in nsim_dev_health_break_write()")

Affected products

• Linux kernel: 3.9 — fixed in 6.18

How to fix

Upgrade to a fixed version: Linux kernel 6.18. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/151bd88859474cdaccc1e4c8b21fbf72dbba2ab4
• https://git.kernel.org/stable/c/5d5f08fd0cd970184376bee07d59f635c8403f63
• https://git.kernel.org/stable/c/a0c2c36d864ef3676b05cfd8c58b72ee3214cb1a
• https://git.kernel.org/stable/c/d381de7fd4cdc928ede96987dc64b133e6480dd6
• https://git.kernel.org/stable/c/f40405ccfb87b71175f2d5d004c0b8a0aebcc2cf

Get alerted when CVE-2025-40193 or the next vulnerability affects your stack