Vulnerability in StackGuard before 1.21 allows remote attackers to bypass the Random and Terminator Canary security mechanisms by using a non-linear attack…

Vulnerability in StackGuard before 1.21 allows remote attackers to bypass the Random and Terminator Canary security mechanisms by using a non-linear attack which directly modifies a pointer to a return address instead of using a buffer overflow to reach the return address entry itself.