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Fencer Vulns
medium 5.5

CVE-2023-53200 json

netfilter: x_tables: fix percpu counter block leak on error path when creating new netns

published 2025-09-15 13 mo ago modified 2026-11-05 3 d ago also EUVD-2023-59883

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

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

netfilter: x_tables: fix percpu counter block leak on error path when creating new netns

Here is the stack where we allocate percpu counter block:

+-< __alloc_percpu +-< xt_percpu_counter_alloc +-< find_check_entry # {arp,ip,ip6}_tables.c +-< translate_table

And it can be leaked on this code path:

+-> ip6t_register_table +-> translate_table # allocates percpu counter block +-> xt_register_table # fails

there is no freeing of the counter block on xt_register_table fail. Note: xt_percpu_counter_free should be called to free it like we do in do_replace through cleanup_entry helper (or in __ip6t_unregister_table).

Probability of hitting this error path is low AFAICS (xt_register_table can only return ENOMEM here, as it is not replacing anything, as we are creating new netns, and it is hard to imagine that all previous allocations succeeded and after that one in xt_register_table failed). But it's worth fixing even the rare leak.

Patch / fix

  • Linux Linux 5.15.100, 6.1.18, 6.2.5, 6.3
  • linux Debian 14, Debian 13, Debian 12 6.1.20-1

debian advisories DEBIAN-CVE-2023-53200

  • linux Ubuntu 22.04 LTS 5.15.0-79.86
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1042.47
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1039.47
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1039.44
  • linux-ibm Ubuntu 22.04 LTS 5.15.0-1035.38
  • linux-kvm Ubuntu 22.04 LTS 5.15.0-1039.44
  • linux-azure Ubuntu 22.04 LTS 5.15.0-1045.52
  • linux-gkeop Ubuntu 22.04 LTS 5.15.0-1025.30

ubuntu advisories UBUNTU-CVE-2023-53200

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-53200 updated cvss 4.1

kernel: netfilter: x_tables: fix percpu counter block leak on error path when creating new netns

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux 10 kernel
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
3 d ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

Classification

Weakness
  • CWE-401 Missing Release of Memory after Effective Lifetime
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.