flex.skl in Will Estes and John Millaway Fast Lexical Analyzer Generator (flex) before…
Priority MEDIUM 40CWE-119Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- — Not recorded in CVSS 2.0
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- Partial · Partial · Partial
- Fix status
- No fix listed
Attack profile from CVSS 2.0 · NVD. Fix status from CNA. Impact type from CWE-119 and the CVSS impact.
Summary
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.
Why it matters now
EPSS 0.04708 91st percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2006-0459
- 2026-10-03 Alias added: GHSA-c6v8-67cp-6v4p
References
More Westes Flex vulnerabilities
- TI-2016-05442 Heap-based buffer overflow in the yy_get_next_buffer function in Flex before 2.6.1 might… CVSS 3.0CRITICAL 9.8
- TI-2019-04480 An issue was discovered in the function mark_beginning_as_normal in nfa.c in flex 2.6.4. CVSS 3.0MEDIUM 5.5
Sources
- CVE-2006-0459 · CVE Program
- CVE-2006-0459 · NVD
- FIRST EPSS
- GHSA-c6v8-67cp-6v4p · GitHub Advisory Database · CC BY 4.0
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