CVE-2026-23072 (GCVE-0-2026-23072)

Vulnerability from cvelistv5 – Published: 2026-02-04 16:07 – Updated: 2026-05-11 21:59
VLAI
Title
l2tp: Fix memleak in l2tp_udp_encap_recv().
Summary
In the Linux kernel, the following vulnerability has been resolved: l2tp: Fix memleak in l2tp_udp_encap_recv(). syzbot reported memleak of struct l2tp_session, l2tp_tunnel, sock, etc. [0] The cited commit moved down the validation of the protocol version in l2tp_udp_encap_recv(). The new place requires an extra error handling to avoid the memleak. Let's call l2tp_session_put() there. [0]: BUG: memory leak unreferenced object 0xffff88810a290200 (size 512): comm "syz.0.17", pid 6086, jiffies 4294944299 hex dump (first 32 bytes): 7d eb 04 0c 00 00 00 00 01 00 00 00 00 00 00 00 }............... 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc babb6a4f): kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline] slab_post_alloc_hook mm/slub.c:4958 [inline] slab_alloc_node mm/slub.c:5263 [inline] __do_kmalloc_node mm/slub.c:5656 [inline] __kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] l2tp_session_create+0x3a/0x3b0 net/l2tp/l2tp_core.c:1778 pppol2tp_connect+0x48b/0x920 net/l2tp/l2tp_ppp.c:755 __sys_connect_file+0x7a/0xb0 net/socket.c:2089 __sys_connect+0xde/0x110 net/socket.c:2108 __do_sys_connect net/socket.c:2114 [inline] __se_sys_connect net/socket.c:2111 [inline] __x64_sys_connect+0x1c/0x30 net/socket.c:2111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 364798056f518b0bf2f17cd9eaf0dd4e856d7393 , < 5cd158a88eef34e7b100cd9b963873d3b4e41b35 (git)
Affected: 364798056f518b0bf2f17cd9eaf0dd4e856d7393 , < d4ce79e6dce2a4a49eebceea7b4caf5dc0f0ef3d (git)
Affected: 364798056f518b0bf2f17cd9eaf0dd4e856d7393 , < 4d10edfd1475b69dbd4c47f34b61a3772ece83ca (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.10
Unaffected: 0 , < 6.10 (semver)
Unaffected: 6.12.68 , ≤ 6.12.* (semver)
Unaffected: 6.18.8 , ≤ 6.18.* (semver)
Unaffected: 6.19 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/l2tp/l2tp_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5cd158a88eef34e7b100cd9b963873d3b4e41b35",
              "status": "affected",
              "version": "364798056f518b0bf2f17cd9eaf0dd4e856d7393",
              "versionType": "git"
            },
            {
              "lessThan": "d4ce79e6dce2a4a49eebceea7b4caf5dc0f0ef3d",
              "status": "affected",
              "version": "364798056f518b0bf2f17cd9eaf0dd4e856d7393",
              "versionType": "git"
            },
            {
              "lessThan": "4d10edfd1475b69dbd4c47f34b61a3772ece83ca",
              "status": "affected",
              "version": "364798056f518b0bf2f17cd9eaf0dd4e856d7393",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/l2tp/l2tp_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.10"
            },
            {
              "lessThan": "6.10",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.68",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.19",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.68",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.8",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19",
                  "versionStartIncluding": "6.10",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nl2tp: Fix memleak in l2tp_udp_encap_recv().\n\nsyzbot reported memleak of struct l2tp_session, l2tp_tunnel,\nsock, etc. [0]\n\nThe cited commit moved down the validation of the protocol\nversion in l2tp_udp_encap_recv().\n\nThe new place requires an extra error handling to avoid the\nmemleak.\n\nLet\u0027s call l2tp_session_put() there.\n\n[0]:\nBUG: memory leak\nunreferenced object 0xffff88810a290200 (size 512):\n  comm \"syz.0.17\", pid 6086, jiffies 4294944299\n  hex dump (first 32 bytes):\n    7d eb 04 0c 00 00 00 00 01 00 00 00 00 00 00 00  }...............\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n  backtrace (crc babb6a4f):\n    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]\n    slab_post_alloc_hook mm/slub.c:4958 [inline]\n    slab_alloc_node mm/slub.c:5263 [inline]\n    __do_kmalloc_node mm/slub.c:5656 [inline]\n    __kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669\n    kmalloc_noprof include/linux/slab.h:961 [inline]\n    kzalloc_noprof include/linux/slab.h:1094 [inline]\n    l2tp_session_create+0x3a/0x3b0 net/l2tp/l2tp_core.c:1778\n    pppol2tp_connect+0x48b/0x920 net/l2tp/l2tp_ppp.c:755\n    __sys_connect_file+0x7a/0xb0 net/socket.c:2089\n    __sys_connect+0xde/0x110 net/socket.c:2108\n    __do_sys_connect net/socket.c:2114 [inline]\n    __se_sys_connect net/socket.c:2111 [inline]\n    __x64_sys_connect+0x1c/0x30 net/socket.c:2111\n    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94\n    entry_SYSCALL_64_after_hwframe+0x77/0x7f"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-11T21:59:27.431Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5cd158a88eef34e7b100cd9b963873d3b4e41b35"
        },
        {
          "url": "https://git.kernel.org/stable/c/d4ce79e6dce2a4a49eebceea7b4caf5dc0f0ef3d"
        },
        {
          "url": "https://git.kernel.org/stable/c/4d10edfd1475b69dbd4c47f34b61a3772ece83ca"
        }
      ],
      "title": "l2tp: Fix memleak in l2tp_udp_encap_recv().",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-23072",
    "datePublished": "2026-02-04T16:07:52.790Z",
    "dateReserved": "2026-01-13T15:37:45.957Z",
    "dateUpdated": "2026-05-11T21:59:27.431Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-23072",
      "date": "2026-09-27",
      "epss": "0.00128",
      "percentile": "0.02077"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "net/l2tp/l2tp_core.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "5cd158a88eef34e7b100cd9b963873d3b4e41b35",
                    "status": "affected",
                    "version": "364798056f518b0bf2f17cd9eaf0dd4e856d7393",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "d4ce79e6dce2a4a49eebceea7b4caf5dc0f0ef3d",
                    "status": "affected",
                    "version": "364798056f518b0bf2f17cd9eaf0dd4e856d7393",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "4d10edfd1475b69dbd4c47f34b61a3772ece83ca",
                    "status": "affected",
                    "version": "364798056f518b0bf2f17cd9eaf0dd4e856d7393",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "net/l2tp/l2tp_core.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.10"
                  },
                  {
                    "lessThan": "6.10",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.68",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.8",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "6.19",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "B360F4B3-2812-43A4-9C53-C15FABD0EBFB",
                    "versionEndExcluding": "6.12.68",
                    "versionStartIncluding": "6.10",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "E65C6E79-7EBE-4C77-93F0-818CF5B38F4E",
                    "versionEndExcluding": "6.18.8",
                    "versionStartIncluding": "6.13",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*",
                    "matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*",
                    "matchCriteriaId": "CAD1FED7-CF48-47BF-AC7D-7B6FA3C065FC",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:*",
                    "matchCriteriaId": "3EF854A1-ABB1-4E93-BE9A-44569EC76C0D",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nl2tp: Fix memleak in l2tp_udp_encap_recv().\n\nsyzbot reported memleak of struct l2tp_session, l2tp_tunnel,\nsock, etc. [0]\n\nThe cited commit moved down the validation of the protocol\nversion in l2tp_udp_encap_recv().\n\nThe new place requires an extra error handling to avoid the\nmemleak.\n\nLet\u0027s call l2tp_session_put() there.\n\n[0]:\nBUG: memory leak\nunreferenced object 0xffff88810a290200 (size 512):\n  comm \"syz.0.17\", pid 6086, jiffies 4294944299\n  hex dump (first 32 bytes):\n    7d eb 04 0c 00 00 00 00 01 00 00 00 00 00 00 00  }...............\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n  backtrace (crc babb6a4f):\n    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]\n    slab_post_alloc_hook mm/slub.c:4958 [inline]\n    slab_alloc_node mm/slub.c:5263 [inline]\n    __do_kmalloc_node mm/slub.c:5656 [inline]\n    __kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669\n    kmalloc_noprof include/linux/slab.h:961 [inline]\n    kzalloc_noprof include/linux/slab.h:1094 [inline]\n    l2tp_session_create+0x3a/0x3b0 net/l2tp/l2tp_core.c:1778\n    pppol2tp_connect+0x48b/0x920 net/l2tp/l2tp_ppp.c:755\n    __sys_connect_file+0x7a/0xb0 net/socket.c:2089\n    __sys_connect+0xde/0x110 net/socket.c:2108\n    __do_sys_connect net/socket.c:2114 [inline]\n    __se_sys_connect net/socket.c:2111 [inline]\n    __x64_sys_connect+0x1c/0x30 net/socket.c:2111\n    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94\n    entry_SYSCALL_64_after_hwframe+0x77/0x7f"
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nl2tp: Solucionar fuga de memoria en l2tp_udp_encap_recv().\n\nsyzbot inform\u00f3 una fuga de memoria de struct l2tp_session, l2tp_tunnel, sock, etc. [0]\n\nEl commit citado movi\u00f3 hacia abajo la validaci\u00f3n de la versi\u00f3n del protocolo en l2tp_udp_encap_recv().\n\nEl nuevo lugar requiere un manejo de errores adicional para evitar la fuga de memoria.\n\nLlamemos a l2tp_session_put() all\u00ed.\n\n[0]:\nERROR: fuga de memoria\nobjeto sin referencia 0xffff88810a290200 (tama\u00f1o 512):\n  comm \u0027syz.0.17\u0027, pid 6086, jiffies 4294944299\n  volcado hexadecimal (primeros 32 bytes):\n    7d eb 04 0c 00 00 00 00 01 00 00 00 00 00 00 00  }...............\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n  rastreo de pila (crc babb6a4f):\n    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]\n    slab_post_alloc_hook mm/slub.c:4958 [inline]\n    slab_alloc_node mm/slub.c:5263 [inline]\n    __do_kmalloc_node mm/slub.c:5656 [inline]\n    __kmalloc_noprof+0x3e0/0x660 mm/slub.c:5669\n    kmalloc_noprof include/linux/slab.h:961 [inline]\n    kzalloc_noprof include/linux/slab.h:1094 [inline]\n    l2tp_session_create+0x3a/0x3b0 net/l2tp/l2tp_core.c:1778\n    pppol2tp_connect+0x48b/0x920 net/l2tp/l2tp_ppp.c:755\n    __sys_connect_file+0x7a/0xb0 net/socket.c:2089\n    __sys_connect+0xde/0x110 net/socket.c:2108\n    __do_sys_connect net/socket.c:2114 [inline]\n    __se_sys_connect net/socket.c:2111 [inline]\n    __x64_sys_connect+0x1c/0x30 net/socket.c:2111\n    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94\n    entry_SYSCALL_64_after_hwframe+0x77/0x7f"
          }
        ],
        "id": "CVE-2026-23072",
        "lastModified": "2026-06-17T10:20:48.840",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2026-02-04T17:16:17.923",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/4d10edfd1475b69dbd4c47f34b61a3772ece83ca"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/5cd158a88eef34e7b100cd9b963873d3b4e41b35"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/d4ce79e6dce2a4a49eebceea7b4caf5dc0f0ef3d"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-401"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2026-06-28T11:14:21+00:00",
      "cve": "CVE-2026-23072",
      "id": "CVE-2026-23072",
      "initial_release_date": "2026-02-04T00:00:00+00:00",
      "product_status:known_affected": "76",
      "product_status:known_not_affected": "198",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: l2tp: Fix memleak in l2tp_udp_encap_recv()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23072.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-11T01:38:20Z",
      "cve": "CVE-2026-23072",
      "id": "CVE-2026-23072",
      "initial_release_date": "2026-02-05T00:25:12Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "399",
      "product_status:known_not_affected": "423",
      "product_status:recommended": "172",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-23072",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-23072.json",
      "version": "12"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • 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.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.