The gnu regular expression code in file 4.20 allows context-dependent attackers to cause a denial of service (CPU consumption) via a crafted document with a large number of line feed characters, which is not well handled by OS/2 REXX regular expressions that use wildcards, as originally reported for AMaViS.

References

• https://nvd.nist.gov/vuln/detail/CVE-2007-2026
• https://bugs.gentoo.org/show_bug.cgi?id=174217
• https://issues.rpath.com/browse/RPL-1311
• http://secunia.com/advisories/24918
• http://secunia.com/advisories/25394
• http://secunia.com/advisories/25544
• http://secunia.com/advisories/25578
• http://sourceforge.net/mailarchive/forum.php?thread_name=755AF709E5B77E6EA58479D5%40foxx.lsit.ucsb.edu&forum_name=amavis-user
• http://www.amavis.org/security/asa-2007-3.txt
• http://www.gentoo.org/security/en/glsa/glsa-200704-13.xml
• http://www.mandriva.com/security/advisories?name=MDKSA-2007:114
• http://www.securityfocus.com/archive/1/469520/30/6420/threaded
• http://www.securityfocus.com/bid/24146
• http://www.vupen.com/english/advisories/2007/2071