CVE-2026-43178 (GCVE-0-2026-43178)

Vulnerability from cvelistv5 – Published: 2026-05-06 11:27 – Updated: 2026-05-08 12:40
VLAI?
Title
procfs: fix possible double mmput() in do_procmap_query()
Summary
In the Linux kernel, the following vulnerability has been resolved: procfs: fix possible double mmput() in do_procmap_query() When user provides incorrectly sized buffer for build ID for PROCMAP_QUERY we return with -ENAMETOOLONG error. After recent changes this condition happens later, after we unlocked mmap_lock/per-VMA lock and did mmput(), so original goto out is now wrong and will double-mmput() mm_struct. Fix by jumping further to clean up only vm_file and name_buf.
Severity ?
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: b9b97e6aeb534315f9646b2090d1a5024c6a4e82 , < f9fe092084cd04deea18747f58a2304026e76aaa (git)
Affected: cbc03ce3e6ce7e21214c3f02218213574c1a2d08 , < 8adaff87db143583e08eec4f4e7788f1ef8af94d (git)
Affected: b5cbacd7f86f4f62b8813688c8e73be94e8e1951 , < 90f5e87c9b75833b9ef3a4415b92c0247f28ab2f (git)
Affected: b5cbacd7f86f4f62b8813688c8e73be94e8e1951 , < 61dc9f776705d6db6847c101b98fa4f0e9eb6fa3 (git)
Create a notification for this product.
    Linux Linux Affected: 6.19
Unaffected: 0 , < 6.19 (semver)
Unaffected: 6.12.75 , ≤ 6.12.* (semver)
Unaffected: 6.18.16 , ≤ 6.18.* (semver)
Unaffected: 6.19.6 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/proc/task_mmu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "f9fe092084cd04deea18747f58a2304026e76aaa",
              "status": "affected",
              "version": "b9b97e6aeb534315f9646b2090d1a5024c6a4e82",
              "versionType": "git"
            },
            {
              "lessThan": "8adaff87db143583e08eec4f4e7788f1ef8af94d",
              "status": "affected",
              "version": "cbc03ce3e6ce7e21214c3f02218213574c1a2d08",
              "versionType": "git"
            },
            {
              "lessThan": "90f5e87c9b75833b9ef3a4415b92c0247f28ab2f",
              "status": "affected",
              "version": "b5cbacd7f86f4f62b8813688c8e73be94e8e1951",
              "versionType": "git"
            },
            {
              "lessThan": "61dc9f776705d6db6847c101b98fa4f0e9eb6fa3",
              "status": "affected",
              "version": "b5cbacd7f86f4f62b8813688c8e73be94e8e1951",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/proc/task_mmu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "lessThan": "6.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.75",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.16",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.6",
              "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": "6.12.75",
                  "versionStartIncluding": "6.12.70",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.16",
                  "versionStartIncluding": "6.18.10",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.6",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nprocfs: fix possible double mmput() in do_procmap_query()\n\nWhen user provides incorrectly sized buffer for build ID for PROCMAP_QUERY\nwe return with -ENAMETOOLONG error.  After recent changes this condition\nhappens later, after we unlocked mmap_lock/per-VMA lock and did mmput(),\nso original goto out is now wrong and will double-mmput() mm_struct.  Fix\nby jumping further to clean up only vm_file and name_buf."
        }
      ],
      "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"
          }
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-08T12:40:59.592Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/f9fe092084cd04deea18747f58a2304026e76aaa"
        },
        {
          "url": "https://git.kernel.org/stable/c/8adaff87db143583e08eec4f4e7788f1ef8af94d"
        },
        {
          "url": "https://git.kernel.org/stable/c/90f5e87c9b75833b9ef3a4415b92c0247f28ab2f"
        },
        {
          "url": "https://git.kernel.org/stable/c/61dc9f776705d6db6847c101b98fa4f0e9eb6fa3"
        }
      ],
      "title": "procfs: fix possible double mmput() in do_procmap_query()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43178",
    "datePublished": "2026-05-06T11:27:51.524Z",
    "dateReserved": "2026-05-01T14:12:55.991Z",
    "dateUpdated": "2026-05-08T12:40:59.592Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-43178",
      "date": "2026-05-09",
      "epss": "0.00012",
      "percentile": "0.01738"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-43178\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-05-06T12:16:36.303\",\"lastModified\":\"2026-05-08T13:16:42.000\",\"vulnStatus\":\"Undergoing Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nprocfs: fix possible double mmput() in do_procmap_query()\\n\\nWhen user provides incorrectly sized buffer for build ID for PROCMAP_QUERY\\nwe return with -ENAMETOOLONG error.  After recent changes this condition\\nhappens later, after we unlocked mmap_lock/per-VMA lock and did mmput(),\\nso original goto out is now wrong and will double-mmput() mm_struct.  Fix\\nby jumping further to clean up only vm_file and name_buf.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/61dc9f776705d6db6847c101b98fa4f0e9eb6fa3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8adaff87db143583e08eec4f4e7788f1ef8af94d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/90f5e87c9b75833b9ef3a4415b92c0247f28ab2f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/f9fe092084cd04deea18747f58a2304026e76aaa\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}


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.



Detection rules are retrieved from Rulezet.