1. Gentoo Linux Security Advisory
| Advisory Reference | GLSA 200603-07 / flex |
| Release Date | March 10, 2006 |
| Latest Revision | March 10, 2006: 01 |
| Impact | normal |
| Exploitable | remote and local |
| Package | Vulnerable versions | Unaffected versions | Architecture(s) |
| sys-devel/flex | < 2.5.33-r1 | >= 2.5.33-r1 | All supported architectures |
Related bugreports: #122940
flex might generate code with a buffer overflow, making applications using such scanners vulnerable to the execution of arbitrary code.
flex is a programming tool used to generate scanners (programs which recognize lexical patterns in text).
Chris Moore discovered a buffer overflow in a special class of lexicographical scanners generated by flex. Only scanners generated by grammars which use either REJECT, or rules with a "variable trailing context" might be at risk.
An attacker could feed malicious input to an application making use of an affected scanner and trigger the buffer overflow, potentially resulting in the execution of arbitrary code.
Avoid using vulnerable grammar in your flex scanners.
All flex users should upgrade to the latest version:
Code Listing 3.1: Resolution |
# emerge --sync # emerge --ask --oneshot --verbose ">=sys-devel/flex-2.5.33-r1" |