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CVE-2026-53219

netfilter: x_tables: avoid leaking percpu counter pointers

published

In the Linux kernel, the following vulnerability has been resolved: netfilter: x_tables: avoid leaking percpu counter pointers The native and compat get-entries paths copy the fixed rule entry header from the kernelized rule blob to userspace before overwriting the entry's counter fields with a sanitized counter snapshot. On SMP kernels, entry->counters.pcnt contains the percpu allocation address used by x_tables rule counters. A caller can provide a userspace buffer that faults during the initial fixed-header copy after pcnt has been copied but before the later sanitized counter copy runs. The syscall then returns -EFAULT while leaving the raw percpu pointer in userspace. Copy only the fixed entry prefix before counters from the kernelized rule blob, then copy the sanitized counter snapshot into the counter field. Apply this ordering to the IPv4, IPv6, and ARP native and compat get-entries implementations so a fault cannot expose the internal percpu counter pointer.

Technical severity5.5 mediumCVSS 3.1 · NVD: [email protected]

Published2026-06-25Source updated 2026-11-10

Collected2026-11-103 attributed sources

Fixes and workarounds

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Affected products and versions

Affected products, source version ranges and reporting authorities
Product	Versions	Authority
Linux Linux	≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < b74ba3343eb44b2cbf7e9665918c287df1d52ebb (affected, git) ≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < 0b35dc8527ccc16b7dc34e8a3164313e68cd4e45 (affected, git) ≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < b28e2fcad3db7e8687b15bc20bced26b5b7c920e (affected, git) ≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < a0d16941adf3a501956d74aefd8d6e217906e79c (affected, git) ≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < 8d67e42ad3b1a95a152541015a07110e06992d6c (affected, git) ≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < 08a3e218064db11f154ad9ad5541751ea7f34ebe (affected, git) ≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < fb0521aff1e10e300d89725cc439d3ea74c828c5 (affected, git) ≥ 71ae0dff02d756e4d2ca710b79f2ff5390029a5f; < f7f2fbb0e893a0238dc464f8d8c0f5609bec584f (affected, git) Other versions: unaffected	CNA: Linux
Linux Linux	4.2 (affected) ≥ 0; < 4.2 (unaffected, semver) ≥ 5.10.259; ≤ 5.10.* (unaffected, semver) ≥ 5.15.210; ≤ 5.15.* (unaffected, semver) ≥ 6.1.176; ≤ 6.1.* (unaffected, semver) ≥ 6.6.143; ≤ 6.6.* (unaffected, semver) ≥ 6.12.94; ≤ 6.12.* (unaffected, semver) ≥ 6.18.36; ≤ 6.18.* (unaffected, semver) ≥ 7.0.13; ≤ 7.0.* (unaffected, semver) ≥ 7.1; ≤ * (unaffected, original_commit_for_fix) Other versions: affected	CNA: Linux
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) Siemens	≥ V3.1.6; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) Siemens	≥ V3.1.7; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) Siemens	≥ V3.1.6; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) Siemens	≥ V3.1.7; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) Siemens	≥ V3.1.6; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) Siemens	≥ V3.1.7; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) Siemens	≥ V3.1.6; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) Siemens	≥ V3.1.7; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem Siemens	≥ 0; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) Siemens	≥ V3.1.6; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) Siemens	≥ V3.1.7; < * (affected, custom) Other versions: unknown	ADP: siemens-SADP

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

NVD applicability configurations (1)

These expressions retain AND/OR operators, negation, and required environmental products. A listed product is not sufficient to establish exposure when additional conditions apply.

[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "5.10.259",
            "versionStartIncluding": "4.2",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "5.15.210",
            "versionStartIncluding": "5.11",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "6.1.176",
            "versionStartIncluding": "5.16",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "6.6.143",
            "versionStartIncluding": "6.2",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "6.12.94",
            "versionStartIncluding": "6.7",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "6.18.36",
            "versionStartIncluding": "6.13",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "7.0.13",
            "versionStartIncluding": "6.19",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:*",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / score	Vector	Authority
3.1 / 5.5 medium	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`	NVD: [email protected]

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

https://git.kernel.org/stable/c/b74ba3343eb44b2cbf7e9665918c287df1d52ebbCNA: Linux
https://git.kernel.org/stable/c/0b35dc8527ccc16b7dc34e8a3164313e68cd4e45CNA: Linux
https://git.kernel.org/stable/c/b28e2fcad3db7e8687b15bc20bced26b5b7c920eCNA: Linux
https://git.kernel.org/stable/c/a0d16941adf3a501956d74aefd8d6e217906e79cCNA: Linux
https://git.kernel.org/stable/c/8d67e42ad3b1a95a152541015a07110e06992d6cCNA: Linux
https://git.kernel.org/stable/c/08a3e218064db11f154ad9ad5541751ea7f34ebeCNA: Linux
https://git.kernel.org/stable/c/fb0521aff1e10e300d89725cc439d3ea74c828c5CNA: Linux
https://git.kernel.org/stable/c/f7f2fbb0e893a0238dc464f8d8c0f5609bec584fCNA: Linux
https://cert-portal.siemens.com/productcert/html/ssa-019113.htmlADP: siemens-SADP
https://cert-portal.siemens.com/productcert/html/ssa-457936.htmlADP: siemens-SADP
https://cert-portal.siemens.com/productcert/html/ssa-784472.htmlADP: siemens-SADP
https://git.kernel.org/stable/c/08a3e218064db11f154ad9ad5541751ea7f34ebe416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://git.kernel.org/stable/c/0b35dc8527ccc16b7dc34e8a3164313e68cd4e45416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://git.kernel.org/stable/c/8d67e42ad3b1a95a152541015a07110e06992d6c416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://git.kernel.org/stable/c/a0d16941adf3a501956d74aefd8d6e217906e79c416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://git.kernel.org/stable/c/b28e2fcad3db7e8687b15bc20bced26b5b7c920e416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://git.kernel.org/stable/c/b74ba3343eb44b2cbf7e9665918c287df1d52ebb416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://git.kernel.org/stable/c/f7f2fbb0e893a0238dc464f8d8c0f5609bec584f416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://git.kernel.org/stable/c/fb0521aff1e10e300d89725cc439d3ea74c828c5416baaa9-dc9f-4396-8d5f-8c081fb06d67 · Patch
https://cert-portal.siemens.com/productcert/html/ssa-019113.html0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
https://cert-portal.siemens.com/productcert/html/ssa-457936.html0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
https://cert-portal.siemens.com/productcert/html/ssa-784472.html0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

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