What’s Vulnerable › Vulnerabilities

CVE-2026-63956: USB: serial: cypress_m8: fix memory corruption with small endpoint

• Severity: high (CVSS 7.8 v3.1)
• 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: 2026-07-19 · updated 2026-10-30
• Weakness: CWE-787

Description

In the Linux kernel, the following vulnerability has been resolved: USB: serial: cypress_m8: fix memory corruption with small endpoint Make sure that the interrupt-out endpoint max packet size is at least eight bytes to avoid user-controlled slab corruption or NULL-pointer dereference should a malicious device report a smaller size.

Affected products

• Linux kernel: from 2.6.26 before 5.10.259; from 5.11 before 5.15.210; from 5.16 before 6.1.176; from 6.2 before 6.6.143; from 6.7 before 6.12.93; from 6.13 before 6.18.35 — fixed in 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.93, 6.18.35
• Linux kernel: 2.6.26 — fixed in 7.1

How to fix

Upgrade to a fixed version: Linux kernel 5.10.259, 5.15.210, 6.1.176, 6.6.143; Linux kernel 7.1. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/1ef25704bd3b625fd151c09feee459479f71ee64
• https://git.kernel.org/stable/c/284105c40fc31fff90cdab8a0377aaeb92f87f0e
• https://git.kernel.org/stable/c/4bcaa59f403dbde6328604a500d65ee8d40975d9
• https://git.kernel.org/stable/c/4fcb22218f0a7229b7ce3b3952fb644def293fa5
• https://git.kernel.org/stable/c/52e18ae0c47c5c89e18fcd8022f287f7cc8802ec
• https://git.kernel.org/stable/c/6c13f3bb652bc8665e709ba07122612586aea648
• https://git.kernel.org/stable/c/ad3d1628a46134276546d7a12fedf04be9979158
• https://git.kernel.org/stable/c/e1a9d791fd66ab2431b9e6f6f835823809869047

Get alerted when CVE-2026-63956 or the next vulnerability affects your stack