CVE-2022-48740 selinux: fix double free of cond_list on error paths

What is CVE-2022-48740?

CVE-2022-48740 is a high-severity use after free vulnerability in Linux kernel, published on 20 Jun 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:

selinux: fix double free of cond_list on error paths

On error path from cond_read_list() and duplicate_policydb_cond_list() the cond_list_destroy() gets called a second time in caller functions, resulting in NULL pointer deref. Fix this by resetting the cond_list_len to 0 in cond_list_destroy(), making subsequent calls a noop.

Also consistently reset the cond_list pointer to NULL after freeing.

[PM: fix line lengths in the description]

Weakness: CWE-415

Which versions are affected by CVE-2022-48740?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-48740?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2022-48740 being exploited?

There is no known exploitation of CVE-2022-48740 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-2022-48740, GHSA-f558-fw4f-vm2c, UBUNTU-CVE-2022-48740.