Summary

The Linux kernel is vulnerable to memory corruption due to improper error handling within the netfilter functionality. A local attacker could exploit this vulnerability in order to elevate their privileges.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. The nft_verdict_init() function allows positive values as drop error within the hook verdict, and hence the nf_hook_slow() function can cause a double free vulnerability when NF_DROP is issued with a drop error which resembles NF_ACCEPT.

Products Affected

• Brocade Fabric OS versions before 9.2.0c, and 9.2.1 through 9.2.1a

Note: Brocade Fabric OS products do not enable the necessary configuration required to enable this vulnerability, and a crafted attack through the use of root level access is required to exploit.

• Brocade ASCG versions before 3.1.0

Products Not Affected

• Brocade SANnav is not affected by this vulnerability
  [VEX Justification: Vulnerable_code_not_in_execute_path]

Solution

• Security update provided in Brocade Fabric OS versions 9.2.0c, 9.2.1a1 and 9.2.2
• Security update provided in Brocade ASCG version 3.1.0

Revision History

Disclaimer

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