Vulnerability-Lookup

GHSA-4VH2-JR7C-6362

Vulnerability from github – Published: 2026-08-10 15:33 – Updated: 2026-08-14 00:31

Details

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

can: raw: add locking for raw flags bitfield

With commit 890e5198a6e5 ("can: raw: use bitfields to store flags in struct raw_sock") the formerly separate integer values have been integrated into a single bitfield. This led to a read-modify-write operation when changing a flag in raw_setsockopt() which now needs a locking to prevent concurrent access.

Instead of adding a lock/unlock hell in each of the flag manipulations this patch introduces a wrapper for a new raw_setsockopt_locked() function analogue to the isotp_setsockopt_locked approach in net/can/isotp.c

[mkl: use Closes tag instead of Link]

Severity

7.8 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-68387"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T13:20:31Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: raw: add locking for raw flags bitfield\n\nWith commit 890e5198a6e5 (\"can: raw: use bitfields to store flags in\nstruct raw_sock\") the formerly separate integer values have been integrated\ninto a single bitfield. This led to a read-modify-write operation when\nchanging a flag in raw_setsockopt() which now needs a locking to prevent\nconcurrent access.\n\nInstead of adding a lock/unlock hell in each of the flag manipulations this\npatch introduces a wrapper for a new raw_setsockopt_locked() function\nanalogue to the isotp_setsockopt[_locked]() approach in net/can/isotp.c\n\n[mkl: use Closes tag instead of Link]",
  "id": "GHSA-4vh2-jr7c-6362",
  "modified": "2026-08-14T00:31:57Z",
  "published": "2026-08-10T15:33:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68387"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/00ba4bf8798242253fefc1fa6a78db1d445fd024"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1e5185c090589f4146d728ab36417d8a5419f127"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/57791aab1129c9405f84bb0882de58967d8b44cd"
    }
  ],
  "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-2026-68387 (GCVE-0-2026-68387)

Vulnerability from cvelistv5 – Published: 2026-08-10 12:04 – Updated: 2026-08-17 05:04

Title

can: raw: add locking for raw flags bitfield

Summary

In the Linux kernel, the following vulnerability has been resolved: can: raw: add locking for raw flags bitfield With commit 890e5198a6e5 ("can: raw: use bitfields to store flags in struct raw_sock") the formerly separate integer values have been integrated into a single bitfield. This led to a read-modify-write operation when changing a flag in raw_setsockopt() which now needs a locking to prevent concurrent access. Instead of adding a lock/unlock hell in each of the flag manipulations this patch introduces a wrapper for a new raw_setsockopt_locked() function analogue to the isotp_setsockopt[_locked]() approach in net/can/isotp.c [mkl: use Closes tag instead of Link]

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

3 references

URL	Tags
https://git.kernel.org/stable/c/00ba4bf8798242253…
https://git.kernel.org/stable/c/57791aab1129c9405…
https://git.kernel.org/stable/c/1e5185c090589f414…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 890e5198a6e5b238627c245fafea1a92670a86cd , < 00ba4bf8798242253fefc1fa6a78db1d445fd024 (git) Affected: 890e5198a6e5b238627c245fafea1a92670a86cd , < 57791aab1129c9405f84bb0882de58967d8b44cd (git) Affected: 890e5198a6e5b238627c245fafea1a92670a86cd , < 1e5185c090589f4146d728ab36417d8a5419f127 (git)
Linux	Linux	Affected: 6.18 Unaffected: 0 , < 6.18 (semver) Unaffected: 6.18.42 , ≤ 6.18.* (semver) Unaffected: 7.1.6 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/can/raw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "00ba4bf8798242253fefc1fa6a78db1d445fd024",
              "status": "affected",
              "version": "890e5198a6e5b238627c245fafea1a92670a86cd",
              "versionType": "git"
            },
            {
              "lessThan": "57791aab1129c9405f84bb0882de58967d8b44cd",
              "status": "affected",
              "version": "890e5198a6e5b238627c245fafea1a92670a86cd",
              "versionType": "git"
            },
            {
              "lessThan": "1e5185c090589f4146d728ab36417d8a5419f127",
              "status": "affected",
              "version": "890e5198a6e5b238627c245fafea1a92670a86cd",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/can/raw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.18"
            },
            {
              "lessThan": "6.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.42",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.6",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: raw: add locking for raw flags bitfield\n\nWith commit 890e5198a6e5 (\"can: raw: use bitfields to store flags in\nstruct raw_sock\") the formerly separate integer values have been integrated\ninto a single bitfield. This led to a read-modify-write operation when\nchanging a flag in raw_setsockopt() which now needs a locking to prevent\nconcurrent access.\n\nInstead of adding a lock/unlock hell in each of the flag manipulations this\npatch introduces a wrapper for a new raw_setsockopt_locked() function\nanalogue to the isotp_setsockopt[_locked]() approach in net/can/isotp.c\n\n[mkl: use Closes tag instead of Link]"
        }
      ],
      "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 - The race is driven entirely through local syscalls on an AF_CAN/CAN_RAW socket \u2014 one thread calling bind() while another calls setsockopt(SOL_CAN_RAW, CAN_RAW_LOOPBACK). No network packet is needed to trigger the corruption, so the attack vector is local.\nAC:L - The attacker controls both sides of the race, holding the same fd and issuing concurrent bind()/setsockopt() from two threads it pins itself, and can loop the attempt indefinitely until the unlocked read-modify-write on the shared bitfield word loses the update to ro-\u003ebound. No condition lies outside attacker control.\nPR:L - can_create() and raw_proto impose no capability check, so any unprivileged local user can open a CAN_RAW socket; a user namespace (unshare -Urn) additionally lets an unprivileged attacker create a vcan device to bind to, so only basic local user access is required.\nUI:N - The attacker performs every step itself \u2014 creating the socket, binding, and racing setsockopt \u2014 with no victim action or cooperation needed at any point.\nS:U - The corruption stays within the kernel\u0027s own memory and security authority, giving standard local privilege escalation rather than crossing a VM, IOMMU, or sandbox boundary.\nC:H - Losing the ro-\u003ebound update makes raw_release() skip raw_disable_allfilters(), leaving a receiver entry holding a raw sk pointer that can_rx_register() never refcounted; later frames drive raw_rcv() to read fd_frames, xl_frames, raw_vcid_opts and count out of freed memory, and the resulting UAF lets an attacker groom the freed slab to disclose kernel memory.\nI:H - The same dangling socket gives write primitives: raw_rcv() writes through this_cpu_ptr(ro-\u003euniq) into already free_percpu\u0027d memory and calls sock_queue_rcv_skb() on the freed sock, so a heap-sprayed replacement object yields attacker-influenced writes and control-flow hijack potential.\nA:H - The use-after-free reliably oopses or panics the kernel when CAN frames hit the stale receiver entry, and the clobber also skips netdev_put() (leaking a device reference that hangs unregistration) and can drive can_rx_unregister() into its \"receive list entry not found\" error path."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:04:34.632Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/00ba4bf8798242253fefc1fa6a78db1d445fd024"
        },
        {
          "url": "https://git.kernel.org/stable/c/57791aab1129c9405f84bb0882de58967d8b44cd"
        },
        {
          "url": "https://git.kernel.org/stable/c/1e5185c090589f4146d728ab36417d8a5419f127"
        }
      ],
      "title": "can: raw: add locking for raw flags bitfield",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-68387",
    "datePublished": "2026-08-10T12:04:06.326Z",
    "dateReserved": "2026-07-30T09:28:09.388Z",
    "dateUpdated": "2026-08-17T05:04:34.632Z",
    "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.

Detection rules are retrieved from Rulezet.

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.

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