__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Flex -- buffer overflow [DSA-1020-1] March 28, 2006 21:00 GMT Number Q-157 ______________________________________________________________________________ PROBLEM: Flex generates code, which allocates insufficient memory, if the grammar contains REJECT statements or trailing context rules. PLATFORM: Debian GNU/Linux 3.1 (sarge) DAMAGE: May lead to a buffer overflow and the execution of arbitrary code. SOLUTION: Apply current patches ______________________________________________________________________________ VULNERABILITY The risk is MEDIUM, may lead to a buffer overflow and the ASSESSMENT: execution of arbitrary code. ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/q-157.shtml ORIGINAL BULLETIN: http://www.debian.org/security/2006/dsa-1020 CVE: http://www.cve.mitre.org/cgi-bin/cvename.cgi?name= CVE-2006-0459 ______________________________________________________________________________ [***** Start DSA-1020-1 *****] Debian Security Advisory DSA-1020-1 flex -- buffer overflow Date Reported: 28 Mar 2006 Affected Packages: flex Vulnerable: Yes Security database references: In Mitre's CVE dictionary: CVE-2006-0459. More information: Chris Moore discovered that flex, a scanner generator, generates code, which allocates insufficient memory, if the grammar contains REJECT statements or trailing context rules. This may lead to a buffer overflow and the execution of arbitrary code. If you use code, which is derived from a vulnerable lex grammar in an untrusted environment you need to regenerate your scanner with the fixed version of flex. The old stable distribution (woody) is not affected by this problem. For the stable distribution (sarge) this problem has been fixed in version 2.5.31-31sarge1. For the unstable distribution (sid) this problem has been fixed in version 2.5.33-1. We recommend that you upgrade your flex package. Fixed in: Debian GNU/Linux 3.1 (sarge) Source: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1.dsc http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1. diff.gz http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31.orig.tar.gz Architecture-independent component: http://security.debian.org/pool/updates/main/f/flex/flex-doc_2.5.31-31sarge1_ all.deb Alpha: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ alpha.deb AMD64: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ amd64.deb ARM: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ arm.deb Intel IA-32: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ i386.deb Intel IA-64: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ ia64.deb HPPA: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ hppa.deb Motorola 680x0: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ m68k.deb Big endian MIPS: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ mips.deb Little endian MIPS: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ mipsel.deb PowerPC: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ powerpc.deb IBM S/390: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ s390.deb Sun Sparc: http://security.debian.org/pool/updates/main/f/flex/flex_2.5.31-31sarge1_ sparc.deb MD5 checksums of the listed files are available in the original advisory. [***** End DSA-1020-1 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Debian Security Advisory for the information contained in this bulletin. _______________________________________________________________________________ CIAC, the Computer Incident Advisory Capability, is the computer security incident response team for the U.S. Department of Energy (DOE) and the emergency backup response team for the National Institutes of Health (NIH). CIAC is located at the Lawrence Livermore National Laboratory in Livermore, California. CIAC is also a founding member of FIRST, the Forum of Incident Response and Security Teams, a global organization established to foster cooperation and coordination among computer security teams worldwide. CIAC services are available to DOE, DOE contractors, and the NIH. 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Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes. 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