{"id":"CVE-2006-0459","url":"https://www.cyber-defence.io/tools/cve/CVE-2006-0459","generatedAt":"2026-10-27T20:40:45.192Z","title":"flex.skl in Will Estes and John Millaway Fast Lexical Analyzer Generator (flex) before 2.5.33 does not allocate enough memory for grammars containing (1) REJECT statements or (2) trailing context rules, which causes flex to generate code that contains a…","description":"flex.skl in Will Estes and John Millaway Fast Lexical Analyzer Generator (flex) before 2.5.33 does not allocate enough memory for grammars containing (1) REJECT statements or (2) trailing context rules, which causes flex to generate code that contains a buffer overflow that might allow context-dependent attackers to execute arbitrary code.","published":"2006-03-29T23:02:00.000Z","lastModified":"2026-06-16T22:20:39.000Z","status":"Modified","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"2.0","score":7.5,"severity":"HIGH","vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P"},"cwe":["CWE-119"],"affected":["westes/flex"],"epss":{"score":0.04708,"percentile":0.91753,"date":"2026-10-26","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 (4.71%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"http://prdownloads.sourceforge.net/flex/flex-2.5.33.tar.bz2?download","tags":["Product"],"source":"secalert@redhat.com"},{"url":"http://secunia.com/advisories/19071","tags":["Patch","Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"http://secunia.com/advisories/19126","tags":["Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"http://secunia.com/advisories/19228","tags":["Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"http://secunia.com/advisories/19424","tags":["Patch","Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"http://securityreason.com/securityalert/570","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://sourceforge.net/mailarchive/forum.php?thread_name=20060223020346.GA11231%40tabitha.home.tldz.org&forum_name=flex-announce","tags":["Release Notes"],"source":"secalert@redhat.com"},{"url":"http://www.gentoo.org/security/en/glsa/glsa-200603-07.xml","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.osvdb.org/23440","tags":["Broken Link","Patch"],"source":"secalert@redhat.com"},{"url":"http://www.securityfocus.com/bid/16896","tags":["Patch","Third Party Advisory","VDB Entry"],"source":"secalert@redhat.com"},{"url":"http://www.us.debian.org/security/2006/dsa-1020","tags":["Patch","Vendor Advisory"],"source":"secalert@redhat.com"},{"url":"http://www.vupen.com/english/advisories/2006/0770","tags":["Broken Link","URL Repurposed"],"source":"secalert@redhat.com"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/24995","tags":["VDB Entry"],"source":"secalert@redhat.com"},{"url":"https://usn.ubuntu.com/260-1/","tags":["Third Party Advisory"],"source":"secalert@redhat.com"},{"url":"http://prdownloads.sourceforge.net/flex/flex-2.5.33.tar.bz2?download","tags":["Product"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/19071","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/19126","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/19228","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/19424","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://securityreason.com/securityalert/570","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://sourceforge.net/mailarchive/forum.php?thread_name=20060223020346.GA11231%40tabitha.home.tldz.org&forum_name=flex-announce","tags":["Release Notes"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.gentoo.org/security/en/glsa/glsa-200603-07.xml","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.osvdb.org/23440","tags":["Broken Link","Patch"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/16896","tags":["Patch","Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.us.debian.org/security/2006/dsa-1020","tags":["Patch","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.vupen.com/english/advisories/2006/0770","tags":["Broken Link","URL Repurposed"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://exchange.xforce.ibmcloud.com/vulnerabilities/24995","tags":["VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://usn.ubuntu.com/260-1/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2006-0459","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."}