CVE-2026-4748 — pf silently ignores certain rules

Description (CNA)

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.

Affected (CNA)

Vendor / product	Versions
FreeBSD / FreeBSD	affected 15.0-RELEASE before p5; affected 14.4-RELEASE before p1; affected 14.3-RELEASE before p10

CWE

CWE-480, CWE-754, CWE-1023

References

https://security.freebsd.org/advisories/FreeBSD-SA-26:09.pf.asc

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.