CVE-2022-49183 net/sched: act_ct: fix ref leak when switching zones

What is CVE-2022-49183?

CVE-2022-49183 is a medium-severity memory corruption vulnerability in Linux kernel, published on 26 Feb 2025. 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:

net/sched: act_ct: fix ref leak when switching zones

When switching zones or network namespaces without doing a ct clear in between, it is now leaking a reference to the old ct entry. That's because tcf_ct_skb_nfct_cached() returns false and tcf_ct_flow_table_lookup() may simply overwrite it.

The fix is to, as the ct entry is not reusable, free it already at tcf_ct_skb_nfct_cached().

Which versions are affected by CVE-2022-49183?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-49183?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2022-49183 being exploited?

There is no known exploitation of CVE-2022-49183 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-2022-49183, GHSA-h8cc-85qr-g7ff, ROOT-OS-DEBIAN-11-CVE-2022-49183, UBUNTU-CVE-2022-49183.