CVE-2026-97939 (GCVE-0-2026-97939)
Vulnerability from cvelistv5
Published
2026-09-25 10:22
Modified
2026-10-21 12:53
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: ipmr: account multicast table and route memory A netadmin in a user+net namespace can create many IPv4 and IPv6 multicast routing tables with MRT_TABLE and MRT6_TABLE. Each unseen id allocates an mr_table via the shared mr_table_alloc(), links it into the per-net list, and leaves it until netns teardown. Those objects were not charged to memcg, so the host unreclaimable slab grows with the table count. Account mr_table allocations with GFP_KERNEL_ACCOUNT and mark the IPv4/IPv6 MFC caches SLAB_ACCOUNT. This matches the established handling of IP addresses, routes and alternate interface names. Unresolved MFC entries are still allocated from softIRQ with GFP_ATOMIC and are not charged. They expire after 10 seconds and are bounded by the socket receive queue; see commit 0079ad8e8dc3 ("ipmr: remove hard code cache_resolve_queue_len limit").
References
Impacted products
Vendor Product Version
Linux Linux Version: f0ad0860d01e47a3ffd220564c5c653b3afbe962
Version: f0ad0860d01e47a3ffd220564c5c653b3afbe962
Version: f0ad0860d01e47a3ffd220564c5c653b3afbe962
Version: f0ad0860d01e47a3ffd220564c5c653b3afbe962
Version: f0ad0860d01e47a3ffd220564c5c653b3afbe962
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/ipmr.c",
            "net/ipv4/ipmr_base.c",
            "net/ipv6/ip6mr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "21e0749e8ef272ac7e3eefe0fa488a5983f4b038",
              "status": "affected",
              "version": "f0ad0860d01e47a3ffd220564c5c653b3afbe962",
              "versionType": "git"
            },
            {
              "lessThan": "ec1c6140394ee87127479bc500a3158b125bf07a",
              "status": "affected",
              "version": "f0ad0860d01e47a3ffd220564c5c653b3afbe962",
              "versionType": "git"
            },
            {
              "lessThan": "0264b3ee09b118fec8a5471b4ca288f8ab84722f",
              "status": "affected",
              "version": "f0ad0860d01e47a3ffd220564c5c653b3afbe962",
              "versionType": "git"
            },
            {
              "lessThan": "d0a2e2a4ee6bfe51e398bfb6921a7d0f4c26bc1c",
              "status": "affected",
              "version": "f0ad0860d01e47a3ffd220564c5c653b3afbe962",
              "versionType": "git"
            },
            {
              "lessThan": "b7ee18725f2292ab554aa96a101ae42d45f008bd",
              "status": "affected",
              "version": "f0ad0860d01e47a3ffd220564c5c653b3afbe962",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/ipv4/ipmr.c",
            "net/ipv4/ipmr_base.c",
            "net/ipv6/ip6mr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.35"
            },
            {
              "lessThan": "2.6.35",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.112",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.53",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.160",
                  "versionStartIncluding": "2.6.35",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.112",
                  "versionStartIncluding": "2.6.35",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.53",
                  "versionStartIncluding": "2.6.35",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.7",
                  "versionStartIncluding": "2.6.35",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "2.6.35",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipmr: account multicast table and route memory\n\nA netadmin in a user+net namespace can create many IPv4 and IPv6\nmulticast routing tables with MRT_TABLE and MRT6_TABLE. Each unseen\nid allocates an mr_table via the shared mr_table_alloc(), links it\ninto the per-net list, and leaves it until netns teardown. Those\nobjects were not charged to memcg, so the host unreclaimable slab\ngrows with the table count.\n\nAccount mr_table allocations with GFP_KERNEL_ACCOUNT and mark the\nIPv4/IPv6 MFC caches SLAB_ACCOUNT. This matches the established\nhandling of IP addresses, routes and alternate interface names.\n\nUnresolved MFC entries are still allocated from softIRQ with\nGFP_ATOMIC and are not charged. They expire after 10 seconds and are\nbounded by the socket receive queue; see commit 0079ad8e8dc3\n(\"ipmr: remove hard code cache_resolve_queue_len limit\")."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-21T12:53:46.494Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/21e0749e8ef272ac7e3eefe0fa488a5983f4b038"
        },
        {
          "url": "https://git.kernel.org/stable/c/ec1c6140394ee87127479bc500a3158b125bf07a"
        },
        {
          "url": "https://git.kernel.org/stable/c/0264b3ee09b118fec8a5471b4ca288f8ab84722f"
        },
        {
          "url": "https://git.kernel.org/stable/c/d0a2e2a4ee6bfe51e398bfb6921a7d0f4c26bc1c"
        },
        {
          "url": "https://git.kernel.org/stable/c/b7ee18725f2292ab554aa96a101ae42d45f008bd"
        }
      ],
      "title": "ipmr: account multicast table and route memory",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-97939",
    "datePublished": "2026-09-25T10:22:52.332Z",
    "dateReserved": "2026-09-25T10:18:58.204Z",
    "dateUpdated": "2026-10-21T12:53:46.494Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.