{"cve":"CVE-2023-6534","nvd":{"published":"2023-12-13T09:15:34.680","modified":"2026-06-17T06:50:56.157","status":"Modified","description":"In versions of FreeBSD 14.0-RELEASE before 14-RELEASE-p2, FreeBSD 13.2-RELEASE before 13.2-RELEASE-p7 and FreeBSD 12.4-RELEASE before 12.4-RELEASE-p9, the pf(4) packet filter incorrectly validates TCP sequence numbers.  This could allow a malicious actor to execute a denial-of-service attack against hosts behind the firewall.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":[],"references":["https://security.freebsd.org/advisories/FreeBSD-SA-23:17.pf.asc","https://security.netapp.com/advisory/ntap-20240112-0007/","https://security.freebsd.org/advisories/FreeBSD-SA-23:17.pf.asc","https://security.netapp.com/advisory/ntap-20240112-0007/"],"products":["freebsd:freebsd"],"source":"nvd","synced_at":"2026-10-19T21:42:34.585441961+00:00"},"epss":{"cve":"CVE-2023-6534","score":0.00742,"percentile":0.54676,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}