CVE-2022-50780
kernel: net: fix UAF issue in nfqnl_nf_hook_drop() when ops_init() failed
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · December 24, 2025
Updated · August 5, 2026
Description
A use-after-free vulnerability was found in the Linux kernel's netfilter queue subsystem. When setting up a new network namespace, if ops->init() fails during ops_init(), the allocated data is freed but the pointer in net->gen remains pointing to the freed memory. When nfqnl_nf_hook_drop() is subsequently called during cleanup, it dereferences this invalid pointer, causing a use-after-free condition.
Statement
This flaw can be triggered by unprivileged users who have the ability to create network namespaces via the unshare() syscall. When namespace initialization fails, the cleanup path accesses freed memory, potentially causing a kernel crash. The vulnerability provides a local denial of service vector on systems where user namespaces are enabled.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-825 · Expired Pointer Dereference