CVE-2022-48933 netfilter: nf_tables: fix memory leak during stateful obj update

What is CVE-2022-48933?

CVE-2022-48933 is a medium-severity denial of service vulnerability in Linux kernel, published on 22 Aug 2024. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

netfilter: nf_tables: fix memory leak during stateful obj update

stateful objects can be updated from the control plane. The transaction logic allocates a temporary object for this purpose.

The ->init function was called for this object, so plain kfree() leaks resources. We must call ->destroy function of the object.

nft_obj_destroy does this, but it also decrements the module refcount, but the update path doesn't increment it.

To avoid special-casing the update object release, do module_get for the update case too and release it via nft_obj_destroy().

Weakness: CWE-401

Which versions are affected by CVE-2022-48933?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-48933?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2022-48933 being exploited?

There is no known exploitation of CVE-2022-48933 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2022-48933, GHSA-92cr-jqq3-99x4, UBUNTU-CVE-2022-48933.