Advisories MDKSA-2006:179: Updated openssh packages fix DoS vulnerabilities

[paul]

Tavis Ormandy of the Google Security Team discovered a Denial of

Service vulnerability in the SSH protocol version 1 CRC compensation

attack detector. This could allow a remote unauthenticated attacker to

trigger excessive CPU utilization by sending a specially crafted SSH

message, which would then deny ssh services to other users or processes

(CVE-2006-4924, CVE-2006-4925). Please note that Mandriva ships with

only SSH protocol version 2 enabled by default.

 

Next, an unsafe signal handler was found by Mark Dowd. This signal

handler was vulnerable to a race condition that could be exploited to

perform a pre-authentication DoS, and theoretically a

pre-authentication remote code execution in the case where some

authentication methods like GSSAPI are enabled (CVE-2006-5051).

 

Updated packages have been patched to correct this issue.