CVE-2026-31729

Description

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: validate connector number in ucsi_notify_common() The connector number extracted from CCI via UCSI_CCI_CONNECTOR() is a 7-bit field (0-127) that is used to index into the connector array in ucsi_connector_change(). However, the array is only allocated for the number of connectors reported by the device (typically 2-4 entries). A malicious or malfunctioning device could report an out-of-range connector number in the CCI, causing an out-of-bounds array access in ucsi_connector_change(). Add a bounds check in ucsi_notify_common(), the central point where CCI is parsed after arriving from hardware, so that bogus connector numbers are rejected before they propagate further.

Is your site exposed to CVE-2026-31729?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0001

Probability of exploitation

0.02%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-129 CWE-129

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.5 — 6.12.81
linux	linux_kernel	6.13 — 6.18.22
linux	linux_kernel	6.19 — 6.19.12
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/98429e9ec89a5e3a204112dfaa2dbe6ca28493a0 https://git.kernel.org/stable/c/d2d8c17ac01a1b1f638ea5d340a884ccc5015186 https://git.kernel.org/stable/c/f4e608fe12b7ac6a4a57176ab0296bb5a110a078 https://git.kernel.org/stable/c/f6dcbf2b024d55549959402f1db6c614e51d52cb

Frequently Asked Questions

What is CVE-2026-31729? +

In the Linux kernel, the following vulnerability has been resolved: usb: typec: ucsi: validate connector number in ucsi_notify_common() The connector number extracted from CCI via UCSI_CCI_CONNECTOR() is a 7-bit field (0-127) that is used to index into the connector array in ucsi_connector_change(). However, the array is only allocated for the number of connectors reported by the device (typically 2-4 entries). A malicious or malfunctioning device could report an out-of-range connector number in the CCI, causing an out-of-bounds array access in ucsi_connector_change(). Add a bounds check in ucsi_notify_common(), the central point where CCI is parsed after arriving from hardware, so that bogus connector numbers are rejected before they propagate further. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2026-31729? +

CVE-2026-31729 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0001, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-31729? +

CVE-2026-31729 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-31729? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-0657

A weakness in Automated Logic and Carrier i-Vu Gen5 router on driver version drv_gen5_106-01-2380, allows malformed packets to be sent …

CVE-2025-66559

Taiko Alethia is an Ethereum-equivalent, permissionless, based rollup designed to scale Ethereum without compromising its fundamental properties. In 2.3.1 and …

CVE-2023-31309

Improper validation in Power Management Firmware (PMFW) may allow an attacker with privileges to pass malformed workload arguments when exporting …

CVE-2024-45569 9.8

Memory corruption while parsing the ML IE due to invalid frame content.

CVE-2024-24563 9.8

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine. Arrays can be keyed by a signed integer, …

CVE-2024-31581 9.8

FFmpeg version n6.1 was discovered to contain an improper validation of array index vulnerability in libavcodec/cbs_h266_syntax_template.c. This vulnerability allows attackers …