Vulnerability-Lookup

GHSA-R4HM-9CRW-6G4M

Vulnerability from github – Published: 2026-04-25 09:30 – Updated: 2026-04-27 15:30

Details

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

batman-adv: avoid OGM aggregation when skb tailroom is insufficient

When OGM aggregation state is toggled at runtime, an existing forwarded packet may have been allocated with only packet_len bytes, while a later packet can still be selected for aggregation. Appending in this case can hit skb_put overflow conditions.

Reject aggregation when the target skb tailroom cannot accommodate the new packet. The caller then falls back to creating a new forward packet instead of appending.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-31683"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-25T09:16:02Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: avoid OGM aggregation when skb tailroom is insufficient\n\nWhen OGM aggregation state is toggled at runtime, an existing forwarded\npacket may have been allocated with only packet_len bytes, while a later\npacket can still be selected for aggregation. Appending in this case can\nhit skb_put overflow conditions.\n\nReject aggregation when the target skb tailroom cannot accommodate the new\npacket. The caller then falls back to creating a new forward packet\ninstead of appending.",
  "id": "GHSA-r4hm-9crw-6g4m",
  "modified": "2026-04-27T15:30:51Z",
  "published": "2026-04-25T09:30:28Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31683"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0b10a8b355c3f71012ce89289ec2c2f5e3bfd6c1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0d4aef630be9d5f9c1227d07669c26c4383b5ad0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0e35db29fc5a97a8553f7c2d3a2ba730e46b1ee8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1ada20331f2df2a942d6b83ae1f04a304b642e2a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/67176c96f325837b0bb3e9538ca2eba414f447d8"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6755347c5f9bdd44dee80f692208b056fcd40a52"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6e40ebb999c2c3d2fbb3cacb61f0384ee6e69075"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eda89a1bae0602aec8314ced299bb243b9f9aeef"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-31683 (GCVE-0-2026-31683)

Vulnerability from cvelistv5 – Published: 2026-04-25 08:47 – Updated: 2026-08-05 12:24

Title

batman-adv: avoid OGM aggregation when skb tailroom is insufficient

Summary

In the Linux kernel, the following vulnerability has been resolved: batman-adv: avoid OGM aggregation when skb tailroom is insufficient When OGM aggregation state is toggled at runtime, an existing forwarded packet may have been allocated with only packet_len bytes, while a later packet can still be selected for aggregation. Appending in this case can hit skb_put overflow conditions. Reject aggregation when the target skb tailroom cannot accommodate the new packet. The caller then falls back to creating a new forward packet instead of appending.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root

References

8 references

URL	Tags
https://git.kernel.org/stable/c/67176c96f325837b0…
https://git.kernel.org/stable/c/0b10a8b355c3f7101…
https://git.kernel.org/stable/c/6755347c5f9bdd44d…
https://git.kernel.org/stable/c/1ada20331f2df2a94…
https://git.kernel.org/stable/c/6e40ebb999c2c3d2f…
https://git.kernel.org/stable/c/0e35db29fc5a97a85…
https://git.kernel.org/stable/c/eda89a1bae0602aec…
https://git.kernel.org/stable/c/0d4aef630be9d5f9c…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < 67176c96f325837b0bb3e9538ca2eba414f447d8 (git) Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < 0b10a8b355c3f71012ce89289ec2c2f5e3bfd6c1 (git) Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < 6755347c5f9bdd44dee80f692208b056fcd40a52 (git) Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < 1ada20331f2df2a942d6b83ae1f04a304b642e2a (git) Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < 6e40ebb999c2c3d2fbb3cacb61f0384ee6e69075 (git) Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < 0e35db29fc5a97a8553f7c2d3a2ba730e46b1ee8 (git) Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < eda89a1bae0602aec8314ced299bb243b9f9aeef (git) Affected: c6c8fea29769d998d94fcec9b9f14d4b52b349d3 , < 0d4aef630be9d5f9c1227d07669c26c4383b5ad0 (git)
Linux	Linux	Affected: 2.6.38 Unaffected: 0 , < 2.6.38 (semver) Unaffected: 5.10.253 , ≤ 5.10.* (semver) Unaffected: 5.15.203 , ≤ 5.15.* (semver) Unaffected: 6.1.167 , ≤ 6.1.* (semver) Unaffected: 6.6.130 , ≤ 6.6.* (semver) Unaffected: 6.12.78 , ≤ 6.12.* (semver) Unaffected: 6.18.20 , ≤ 6.18.* (semver) Unaffected: 6.19.10 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/batman-adv/bat_iv_ogm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "67176c96f325837b0bb3e9538ca2eba414f447d8",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            },
            {
              "lessThan": "0b10a8b355c3f71012ce89289ec2c2f5e3bfd6c1",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            },
            {
              "lessThan": "6755347c5f9bdd44dee80f692208b056fcd40a52",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            },
            {
              "lessThan": "1ada20331f2df2a942d6b83ae1f04a304b642e2a",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            },
            {
              "lessThan": "6e40ebb999c2c3d2fbb3cacb61f0384ee6e69075",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            },
            {
              "lessThan": "0e35db29fc5a97a8553f7c2d3a2ba730e46b1ee8",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            },
            {
              "lessThan": "eda89a1bae0602aec8314ced299bb243b9f9aeef",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            },
            {
              "lessThan": "0d4aef630be9d5f9c1227d07669c26c4383b5ad0",
              "status": "affected",
              "version": "c6c8fea29769d998d94fcec9b9f14d4b52b349d3",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/batman-adv/bat_iv_ogm.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.38"
            },
            {
              "lessThan": "2.6.38",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.253",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.203",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.167",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.130",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.78",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.20",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.253",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.203",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.167",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.130",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.78",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.20",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.10",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "2.6.38",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: avoid OGM aggregation when skb tailroom is insufficient\n\nWhen OGM aggregation state is toggled at runtime, an existing forwarded\npacket may have been allocated with only packet_len bytes, while a later\npacket can still be selected for aggregation. Appending in this case can\nhit skb_put overflow conditions.\n\nReject aggregation when the target skb tailroom cannot accommodate the new\npacket. The caller then falls back to creating a new forward packet\ninstead of appending."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - A fully attacker-controlled trigger requires local control of batman-adv setup and the OGM aggregation toggle while injecting OGM traffic. Adjacent OGM frames can reach an existing mesh, but that path depends on a runtime aggregation toggle not controlled by the packet sender.\nAC:L - With local namespace control, the attacker can create the mesh setup, toggle aggregation, and send OGM traffic to deterministically reach the undersized queued skb append. No uncontrolled race or probabilistic condition is required in that scenario.\nPR:L - The required configuration control is CAP_NET_ADMIN, but batman-adv generic netlink uses namespace-capable admin permission, so an unprivileged local user can obtain it in a user namespace. No real init-namespace root privilege is required for that path.\nUI:N - Exploitation does not require a victim user to open a file, mount anything, or otherwise interact once the attacker controls the local namespace setup. The attacker can drive the trigger directly.\nS:U - The vulnerability corrupts or crashes kernel networking state within the same host kernel security authority. It does not cross a VM, IOMMU, or separate sandbox boundary by itself.\nC:H - The missing tailroom check creates an out-of-bounds skb append condition in kernel memory. Although common kernels may hit skb_over_panic first, the underlying memory-safety condition is defensibly scored as capable of exposing kernel data.\nI:H - The vulnerable path appends attacker-controlled OGM bytes past the allocated skb tailroom when the guard is absent. As a kernel out-of-bounds write condition, this is defensibly scored as high integrity impact.\nA:H - At minimum, insufficient tailroom reaches skb_put overflow handling, which triggers a BUG/oops/panic class failure. This can crash or destabilize the kernel, causing high availability impact."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:24:28.913Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/67176c96f325837b0bb3e9538ca2eba414f447d8"
        },
        {
          "url": "https://git.kernel.org/stable/c/0b10a8b355c3f71012ce89289ec2c2f5e3bfd6c1"
        },
        {
          "url": "https://git.kernel.org/stable/c/6755347c5f9bdd44dee80f692208b056fcd40a52"
        },
        {
          "url": "https://git.kernel.org/stable/c/1ada20331f2df2a942d6b83ae1f04a304b642e2a"
        },
        {
          "url": "https://git.kernel.org/stable/c/6e40ebb999c2c3d2fbb3cacb61f0384ee6e69075"
        },
        {
          "url": "https://git.kernel.org/stable/c/0e35db29fc5a97a8553f7c2d3a2ba730e46b1ee8"
        },
        {
          "url": "https://git.kernel.org/stable/c/eda89a1bae0602aec8314ced299bb243b9f9aeef"
        },
        {
          "url": "https://git.kernel.org/stable/c/0d4aef630be9d5f9c1227d07669c26c4383b5ad0"
        }
      ],
      "title": "batman-adv: avoid OGM aggregation when skb tailroom is insufficient",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31683",
    "datePublished": "2026-04-25T08:47:00.334Z",
    "dateReserved": "2026-03-09T15:48:24.130Z",
    "dateUpdated": "2026-08-05T12:24:28.913Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

Action not permitted

GHSA-R4HM-9CRW-6G4M

CVE-2026-31683 (GCVE-0-2026-31683)

Tags

Sightings

Nomenclature

Related by attack behaviour