CVE-2023-42756 Kernel: netfilter: race condition between ipset_cmd_add and ipset_cmd_swap

What is CVE-2023-42756?

CVE-2023-42756 is a medium-severity vulnerability in Debian Debian Linux, published on 28 Sep 2023. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A flaw was found in the Netfilter subsystem of the Linux kernel. A race condition between IPSET_CMD_ADD and IPSET_CMD_SWAP can lead to a kernel panic due to the invocation of `__ip_set_put` on a wrong `set`. This issue may allow a local user to crash the system.

Weakness: CWE-362

Which versions are affected by CVE-2023-42756?

It affects 4 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Linux kernel, Redhat Enterprise Linux.

How do I fix CVE-2023-42756?

Apply the vendor's patch.

Is CVE-2023-42756 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-42756 exists.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-30055, BELL-CVE-2023-42756, DEBIAN-CVE-2023-42756, GHSA-9fpq-xxr8-j37x, UBUNTU-CVE-2023-42756.