What’s Vulnerable › Vulnerabilities

CVE-2026-63959: usb: typec: tcpm/tcpci_maxim: validate header NDO against RX_BYTE_CNT

• Severity: medium (CVSS 5.5 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

Description

In the Linux kernel, the following vulnerability has been resolved: usb: typec: tcpm/tcpci_maxim: validate header NDO against RX_BYTE_CNT A broken/malicious port can transmit a CRC-valid frame whose header advertises up to seven data objects but whose body carries fewer than that. Check for this, and rightfully reject the message, instead of reading from uninitialized stack memory.

Affected products

• Linux kernel: from 5.10 before 6.1.191; from 6.6 before 6.6.143; from 6.7 before 6.12.93; from 6.13 before 6.18.35; from 6.19 before 7.0.12; 7.1-rc1, 7.1-rc2, 7.1-rc3, 7.1-rc4, 7.1-rc5 — fixed in 6.1.191, 6.6.143, 6.12.93, 6.18.35, 7.0.12
• Linux: 5.10 — fixed in 7.1

How to fix

Upgrade to a fixed version: Linux kernel 6.1.191, 6.6.143, 6.12.93, 6.18.35; Linux 7.1. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/0af00f1459f5dd757f0d392f8caa38039561ac62
• https://git.kernel.org/stable/c/8a8cd4790b08c9f79ea2250b3bd933fd79f67e56
• https://git.kernel.org/stable/c/9b496e3371c04f0a03b7faa5d2442536d00e3998
• https://git.kernel.org/stable/c/aa2f716327be1818e1cb156da8a2844804aaec2f
• https://git.kernel.org/stable/c/c4ab8e2d4432abb646c5c0687f8dab173da901f9
• https://git.kernel.org/stable/c/dc17721d42e6d89f63572e63add8306a0e15eb3c

Get alerted when CVE-2026-63959 or the next vulnerability affects your stack