Cyber Resilience

CVE-2026-31729

Linux Kernel 5.5 – 6.12.81

Published
01 May 2026
Modified
07 May 2026
Patch / advisory
View advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0013 3th percentile
Risk Priority 54 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-31729 is a high-severity Improper Validation of Array Index (CWE-129) vulnerability in Linux Linux Kernel. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

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…

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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.

CWE(s)
CWE-129

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-38631Same product: Linux Linux Kernel
CVE-2024-26971Same product: Linux Linux Kernel
CVE-2023-52807Same product: Linux Linux Kernel
CVE-2025-71203Same product: Linux Linux Kernel
CVE-2025-38013Same product: Linux Linux Kernel
CVE-2025-71143Same product: Linux Linux Kernel
CVE-2023-52799Same product: Linux Linux Kernel
CVE-2024-42088Same product: Linux Linux Kernel
CVE-2024-38542Same product: Linux Linux Kernel
CVE-2025-21692Same product: Linux Linux Kernel

Affected Assets

linux
linux kernel
7.0 · 5.5 — 6.12.81 · 6.13 — 6.18.22 · 6.19 — 6.19.12

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and bounds checking that prevent improper array indexing.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development can detect out-of-bounds array access but does not prevent the weakness by itself.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle mandates input validation and bounds checking that directly prevents improper array indexing.

A.8.26 Application security requirements partial match
prevents

Application security requirements include validation of untrusted input used for indexing or addressing memory structures.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles encourage defensive coding patterns that reduce index-related vulnerabilities.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly require bounds checking and validation of array indices derived from untrusted data.

References