CVE intelligence

CVE-2026-31623

Vulnerability intelligence

Published Apr 24, 2026Sources checked Nov 12, 2026

5.5MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-31623 and is rated Medium severity with a CVSS score of 5.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 25, 2026

CBL-Mariner Releases Release Notes

Vendor-listed releases

6.6.137.1-1

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-31623?

In the Linux kernel, the following vulnerability has been resolved:

net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete()

A malicious USB device claiming to be a CDC Phonet modem can overflow the skb_shared_info->frags[] array by sending an unbounded sequence of full-page bulk transfers.

Drop the skb and increment the length error when the frag limit is reached. This matches the same fix that commit f0813bcd2d9d ("net: wwan: t7xx: fix potential skb->frags overflow in RX path") did for the t7xx driver.

Source: NVD