{"id":"CVE-2026-4748","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-4748","generatedAt":"2026-10-28T07:04:14.444Z","title":"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.","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.\n\nSome 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.\n\nAffected rules are silently ignored, which can lead to unexpected behaviour including over- and underblocking.","published":"2026-04-01T07:16:02.000Z","lastModified":"2026-06-17T10:57:10.000Z","status":"Analyzed","sourceIdentifier":"secteam@freebsd.org","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},"cwe":["CWE-480","CWE-754","CWE-1023"],"affected":["freebsd/freebsd"],"epss":{"score":0.0025,"percentile":0.16271,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.25%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://security.freebsd.org/advisories/FreeBSD-SA-26:09.pf.asc","tags":["Vendor Advisory"],"source":"secteam@freebsd.org"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-4748","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}