The MessageDigest.isEqual function in Java Runtime Environment (JRE) in Sun Java SE in JDK and JRE 5.0 before Update 22, JDK and JRE 6 before Update 17, SDK and JRE 1.3.x before 1.3.1_27, and SDK and JRE 1.4.x before 1.4.2_24 allows remote attackers to spoof HMAC-based digital signatures, and possibly bypass authentication, via unspecified vectors related to "timing attack vulnerabilities," aka Bug Id 6863503.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7913
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7549
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12112
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11847
http://www.vupen.com/english/advisories/2009/3131
http://www.securityfocus.com/bid/36881
http://www.redhat.com/support/errata/RHSA-2009-1694.html
http://www.oracle.com/technetwork/topics/security/cpujan2010-084891.html
http://www.mandriva.com/security/advisories?name=MDVSA-2010:084
http://support.apple.com/kb/HT3970
http://support.apple.com/kb/HT3969
http://sunsolve.sun.com/search/document.do?assetkey=1-66-270475-1
http://security.gentoo.org/glsa/glsa-200911-02.xml
http://secunia.com/advisories/37841
http://secunia.com/advisories/37581
http://secunia.com/advisories/37386
http://secunia.com/advisories/37239
http://secunia.com/advisories/37231
http://marc.info/?l=bugtraq&m=134254866602253&w=2
http://marc.info/?l=bugtraq&m=131593453929393&w=2
http://marc.info/?l=bugtraq&m=126566824131534&w=2
http://lists.opensuse.org/opensuse-security-announce/2009-11/msg00010.html
http://lists.apple.com/archives/security-announce/2009/Dec/msg00001.html
http://lists.apple.com/archives/security-announce/2009/Dec/msg00000.html