Summary

Security Advisory ID : BSA-2019-828

Component : TCP SACK

Revision : 2.0

An excessive resource consumption flaw was found in the way the Linux kernel's networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel's socket buffer (SKB) data structure becomes fragmented, which leads to increased resource utilization to traverse and process these fragments as further SACK segments are received on the same TCP connection. A remote attacker could use this flaw to cause a denial of service (DoS) by sending a crafted sequence of SACK segments on a TCP connection.

Affected Products
Security update provided in Brocade Fabric OS v8.2.2c, FOS v7.4.2g, FOS v8.2.0_CBN3, FOS v8.2.1e, FOS v8.1.2k, FOS v9.0.0 and upper releases. 

Products Confirmed Not Vulnerable
No other Brocade Fibre Channel technology products from Broadcom are currently known to be affected by this vulnerability.

Revision History

Version	Change	Date
1.0	Initial Publication	Jul 2, 2019
2.0	Affected products updated	Feb 5, 2021