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Gentoo Linux Security Advisory GLSA 200603-07 |
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http://security.gentoo.org/ |
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Severity: Normal |
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Title: flex: Potential insecure code generation |
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Date: March 10, 2006 |
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Bugs: #122940 |
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ID: 200603-07 |
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Synopsis |
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======== |
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|
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flex might generate code with a buffer overflow, making applications |
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using such scanners vulnerable to the execution of arbitrary code. |
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Background |
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========== |
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|
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flex is a programming tool used to generate scanners (programs which |
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recognize lexical patterns in text). |
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|
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Affected packages |
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================= |
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|
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------------------------------------------------------------------- |
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Package / Vulnerable / Unaffected |
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------------------------------------------------------------------- |
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1 sys-devel/flex < 2.5.33-r1 >= 2.5.33-r1 |
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Description |
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=========== |
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|
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Chris Moore discovered a buffer overflow in a special class of |
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lexicographical scanners generated by flex. Only scanners generated by |
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grammars which use either REJECT, or rules with a "variable trailing |
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context" might be at risk. |
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|
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Impact |
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====== |
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|
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An attacker could feed malicious input to an application making use of |
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an affected scanner and trigger the buffer overflow, potentially |
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resulting in the execution of arbitrary code. |
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Workaround |
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========== |
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Avoid using vulnerable grammar in your flex scanners. |
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Resolution |
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========== |
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All flex users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=sys-devel/flex-2.5.33-r1" |
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References |
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========== |
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[ 1 ] CVE-2006-0459 |
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http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-0459 |
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Availability |
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============ |
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This GLSA and any updates to it are available for viewing at |
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the Gentoo Security Website: |
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http://security.gentoo.org/glsa/glsa-200603-07.xml |
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Concerns? |
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========= |
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Security is a primary focus of Gentoo Linux and ensuring the |
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confidentiality and security of our users machines is of utmost |
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importance to us. Any security concerns should be addressed to |
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security@g.o or alternatively, you may file a bug at |
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http://bugs.gentoo.org. |
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License |
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======= |
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Copyright 2006 Gentoo Foundation, Inc; referenced text |
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belongs to its owner(s). |
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|
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The contents of this document are licensed under the |
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Creative Commons - Attribution / Share Alike license. |
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http://creativecommons.org/licenses/by-sa/2.0 |
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