FKIE_CVE-2026-23456

Vulnerability from fkie_nvd - Published: 2026-04-03 16:16 - Updated: 2026-10-19 19:17
Severity
8.2 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case In decode_int(), the CONS case calls get_bits(bs, 2) to read a length value, then calls get_uint(bs, len) without checking that len bytes remain in the buffer. The existing boundary check only validates the 2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint() reads. This allows a malformed H.323/RAS packet to cause a 1-4 byte slab-out-of-bounds read. Add a boundary check for len bytes after get_bits() and before get_uint().
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1e3a3593162c96e8a8de48b1e14f60c3b57fca8aPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/41b417ff73a24b2c68134992cc44c88db27f482dPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/52235bf88159a1ef16434ab49e47e99c8a09ab20Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6bce72daeccca9aa1746e92d6c3d4784e71f2ebbPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/774a434f8c9c8602a976b2536f65d0172a07f4d2Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a2cd54b9348e485d338b3c132338a4410c99afafPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c95dc674ebf01ecfb40388b6facfc89b81fed3b7Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fb6c3596823ec5dd09c2123340330d7448f51a59Patch
0b142b55-0307-4c5a-b3c9-f314f3fb7c5ehttps://cert-portal.siemens.com/productcert/html/ssa-019113.html
0b142b55-0307-4c5a-b3c9-f314f3fb7c5ehttps://cert-portal.siemens.com/productcert/html/ssa-082556.html
0b142b55-0307-4c5a-b3c9-f314f3fb7c5ehttps://cert-portal.siemens.com/productcert/html/ssa-457936.html
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
To clipboard 

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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case\n\nIn decode_int(), the CONS case calls get_bits(bs, 2) to read a length\nvalue, then calls get_uint(bs, len) without checking that len bytes\nremain in the buffer. The existing boundary check only validates the\n2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint()\nreads. This allows a malformed H.323/RAS packet to cause a 1-4 byte\nslab-out-of-bounds read.\n\nAdd a boundary check for len bytes after get_bits() and before\nget_uint()."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnetfilter: nf_conntrack_h323: correcci\u00f3n de lectura fuera de l\u00edmites (OOB) en el caso CONS de decode_int()\n\nEn decode_int(), el caso CONS llama a get_bits(bs, 2) para leer un valor de longitud, luego llama a get_uint(bs, len) sin comprobar que len bytes permanezcan en el b\u00fafer. La comprobaci\u00f3n de l\u00edmites existente solo valida los 2 bits para get_bits(), no los 1-4 bytes subsiguientes que lee get_uint(). Esto permite que un paquete H.323/RAS malformado cause una lectura fuera de l\u00edmites de slab de 1-4 bytes.\n\nA\u00f1adir una comprobaci\u00f3n de l\u00edmites para len bytes despu\u00e9s de get_bits() y antes de get_uint()."
    }
  ],
  "id": "CVE-2026-23456",
  "lastModified": "2026-10-19T19:17:49.450",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 4.2,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
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    "ssvcV203": [
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        "ssvcData": {
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          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-10-16T15:08:25.282768Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-04-03T16:16:32.300",
  "references": [
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      "tags": [
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    {
      "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
    },
    {
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      "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
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  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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