IT

Tracker / CVE-2026-31681

CVE-2026-31681

Medium 5.5

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_multiport: validate range encoding in checkentry ports_match_v1() treats any non-zero pflags entry as the start of a port range and unconditionally consumes the next ports[] element as the range end. The checkentry path currently validates protocol, flags and count, but it does not validate the range encoding itself. As a result, malformed rules can mark the last slot as a range start or place two range starts back to back, leaving ports_match_v1() to step past the last valid ports[] element while interpreting the rule. Reject malformed multiport v1 rules in checkentry by validating that each range start has a following element and that the following element is not itself marked as another range start.

Affected products and versions

linux linux_kernel
linux linux_kernel · 2.6.17 → 6.6.136
linux linux_kernel · 6.13 → 6.18.24
linux linux_kernel · 6.19 → 6.19.14
linux linux_kernel · 6.7 → 6.12.83

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References