CVE-2022-48748

In the Linux kernel, the following vulnerability has been resolved:

net: bridge: vlan: fix memory leak in __allowed_ingress

When using per-vlan state, if vlan snooping and stats are disabled, untagged or priority-tagged ingress frame will go to check pvid state. If the port state is forwarding and the pvid state is not learning/forwarding, untagged or priority-tagged frame will be dropped but skb memory is not freed. Should free skb when __allowed_ingress returns false.

Weakness

The product does not properly control the allocation and maintenance of a limited resource.

Affected Software

Potential Mitigations

• Mitigation of resource exhaustion attacks requires that the target system either:

• The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.

• The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/147.html
• https://cwe.mitre.org/data/definitions/227.html
• https://cwe.mitre.org/data/definitions/492.html

References

• https://git.kernel.org/stable/c/14be8d448fca6fe7b2a413831eedd55aef6c6511
• https://git.kernel.org/stable/c/446ff1fc37c74093e81db40811a07b5a19f1d797
• https://git.kernel.org/stable/c/c5e216e880fa6f2cd9d4a6541269377657163098
• https://git.kernel.org/stable/c/fd20d9738395cf8e27d0a17eba34169699fccdff
• https://git.kernel.org/stable/c/14be8d448fca6fe7b2a413831eedd55aef6c6511
• https://git.kernel.org/stable/c/446ff1fc37c74093e81db40811a07b5a19f1d797
• https://git.kernel.org/stable/c/c5e216e880fa6f2cd9d4a6541269377657163098
• https://git.kernel.org/stable/c/fd20d9738395cf8e27d0a17eba34169699fccdff