{"cve":"CVE-2011-4539","nvd":{"published":"2011-12-08T11:55:02.407","modified":"2026-06-16T23:35:00.860","status":"Modified","description":"dhcpd in ISC DHCP 4.x before 4.2.3-P1 and 4.1-ESV before 4.1-ESV-R4 does not properly handle regular expressions in dhcpd.conf, which allows remote attackers to cause a denial of service (daemon crash) via a crafted request packet.","cvss_v4":null,"cvss_v3":null,"cwes":["CWE-20"],"references":["http://lists.fedoraproject.org/pipermail/package-announce/2011-December/070980.html","http://lists.fedoraproject.org/pipermail/package-announce/2012-January/071549.html","http://lists.opensuse.org/opensuse-updates/2011-12/msg00006.html","http://secunia.com/advisories/47153","http://secunia.com/advisories/47178"],"products":["canonical:ubuntu_linux","debian:debian_linux","isc:dhcp"],"source":"nvd","synced_at":"2026-10-19T19:59:31.623151214+00:00"},"epss":{"cve":"CVE-2011-4539","score":0.15219,"percentile":0.96757,"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."]}