PSIRT Advisories
Linux kernel - challenge ack information leak
Summary
net/ipv4/tcp_input.c in certain Linux kernel versions does not properly determine the rate of challenge ACK segments, which makes it easier for remote attackers to hijack TCP sessions via a blind in-window attack.
Affected Products
FortiOS versions
- 5.2.8 and below
- 5.4.0 & 5.4.1
Solutions
For FortiOS, upgrade to versions
- 5.2.9 or
- 5.4.2 or
- 5.6.0
- 5.4.2