CVE-2026-4748

High

Description

A regression in the way hashes were calculated caused rules containing the address range syntax (x.x.x.x - y.y.y.y) that only differ in the address range(s) involved to be silently dropped as duplicates. Only the first of such rules is actually loaded into pf. Ranges expressed using the address[/mask-bits] syntax were not affected. Some keywords representing actions taken on a packet-matching rule, such as 'log', 'return tll', or 'dnpipe', may suffer from the same issue. It is unlikely that users have such configurations, as these rules would always be redundant. Affected rules are silently ignored, which can lead to unexpected behaviour including over- and underblocking.

SeverityHigh
CVSS7.5
Exploit probability—
ProductFreebsd
PublishedApr 1, 2026
First seenApr 1, 2026

How to fix

Update
  • freebsd freebsd14.4 or later

Affected products

ProductAffected versionsFixed in
freebsd freebsd14.0 ≤ v < 14.4, 14.3, 14.4, 15.014.4

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