CVE-2006-0459
CVE-2006-0459 is a high-severity vulnerability in Westes Flex with a CVSS 2.0 base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.
Key facts
- Severity: High (CVSS 2.0 base score 7.5)
- EPSS exploit prediction: 5% (91st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Westes Flex
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2006-0459?
- 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.
- How severe is CVE-2006-0459?
- CVE-2006-0459 has a CVSS 2.0 base score of 7.5, rated high severity.
- Is CVE-2006-0459 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2006-0459?
- CVE-2006-0459 affects Westes Flex. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2006-0459?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2006-0459 published?
- CVE-2006-0459 was published on 2006-03-29 and last updated on 2026-06-16.
References
- http://prdownloads.sourceforge.net/flex/flex-2.5.33.tar.bz2?download
- http://secunia.com/advisories/19071
- http://secunia.com/advisories/19126
- http://secunia.com/advisories/19228
- http://secunia.com/advisories/19424
- http://securityreason.com/securityalert/570
- http://sourceforge.net/mailarchive/forum.php?thread_name=20060223020346.GA11231%40tabitha.home.tldz.org&forum_name=flex-announce
- http://www.gentoo.org/security/en/glsa/glsa-200603-07.xml
- http://www.osvdb.org/23440
- http://www.securityfocus.com/bid/16896
- http://www.us.debian.org/security/2006/dsa-1020
- http://www.vupen.com/english/advisories/2006/0770
- https://exchange.xforce.ibmcloud.com/vulnerabilities/24995
- https://usn.ubuntu.com/260-1/
Affected products (1)
- cpe:2.3:a:westes:flex:*:*:*:*:*:*:*:*
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