Vulnerability-Lookup

FKIE_CVE-2026-45927

Vulnerability from fkie_nvd - Published: 2026-05-27 14:17 - Updated: 2026-05-27 14:48

Severity

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: Require frozen map for calculating map hash Currently, bpf_map_get_info_by_fd calculates and caches the hash of the map regardless of the map's frozen state. This leads to a TOCTOU bug where userspace can call BPF_OBJ_GET_INFO_BY_FD to cache the hash and then modify the map contents before freezing. Therefore, a trusted loader can be tricked into verifying the stale hash while loading the modified contents. Fix this by returning -EPERM if the map is not frozen when the hash is requested. This ensures the hash is only generated for the final, immutable state of the map.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7752d36343862323bbeea4ce3adf0ec2ed86e122
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a2c86aa621c22f2a7e26c654f936d65cfff0aa91
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/f415e114b58fe02c41191e47f24bdabb438daf72

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Require frozen map for calculating map hash\n\nCurrently, bpf_map_get_info_by_fd calculates and caches the hash of the\nmap regardless of the map\u0027s frozen state.\n\nThis leads to a TOCTOU bug where userspace can call\nBPF_OBJ_GET_INFO_BY_FD to cache the hash and then modify the map\ncontents before freezing.\n\nTherefore, a trusted loader can be tricked into verifying the stale hash\nwhile loading the modified contents.\n\nFix this by returning -EPERM if the map is not frozen when the hash is\nrequested. This ensures the hash is only generated for the final,\nimmutable state of the map."
    }
  ],
  "id": "CVE-2026-45927",
  "lastModified": "2026-05-27T14:48:03.013",
  "metrics": {},
  "published": "2026-05-27T14:17:08.583",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/7752d36343862323bbeea4ce3adf0ec2ed86e122"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a2c86aa621c22f2a7e26c654f936d65cfff0aa91"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f415e114b58fe02c41191e47f24bdabb438daf72"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}

CVE-2026-45927 (GCVE-0-2026-45927)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:17 – Updated: 2026-05-27 12:17

Title

bpf: Require frozen map for calculating map hash

Summary

Severity

No CVSS data available.

Assigner

Linux

References

3 references

URL	Tags
https://git.kernel.org/stable/c/7752d36343862323b…
https://git.kernel.org/stable/c/f415e114b58fe02c4…
https://git.kernel.org/stable/c/a2c86aa621c22f2a7…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: ea2e6467ac36bf3d785defc89e58269b15d182f7 , < 7752d36343862323bbeea4ce3adf0ec2ed86e122 (git) Affected: ea2e6467ac36bf3d785defc89e58269b15d182f7 , < f415e114b58fe02c41191e47f24bdabb438daf72 (git) Affected: ea2e6467ac36bf3d785defc89e58269b15d182f7 , < a2c86aa621c22f2a7e26c654f936d65cfff0aa91 (git)
Linux	Linux	Affected: 6.18 Unaffected: 0 , < 6.18 (semver) Unaffected: 6.18.14 , ≤ 6.18.* (semver) Unaffected: 6.19.4 , ≤ 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": [
            "kernel/bpf/syscall.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7752d36343862323bbeea4ce3adf0ec2ed86e122",
              "status": "affected",
              "version": "ea2e6467ac36bf3d785defc89e58269b15d182f7",
              "versionType": "git"
            },
            {
              "lessThan": "f415e114b58fe02c41191e47f24bdabb438daf72",
              "status": "affected",
              "version": "ea2e6467ac36bf3d785defc89e58269b15d182f7",
              "versionType": "git"
            },
            {
              "lessThan": "a2c86aa621c22f2a7e26c654f936d65cfff0aa91",
              "status": "affected",
              "version": "ea2e6467ac36bf3d785defc89e58269b15d182f7",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/syscall.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": "6.18.14",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.4",
              "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": "6.18.14",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.4",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.18",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Require frozen map for calculating map hash\n\nCurrently, bpf_map_get_info_by_fd calculates and caches the hash of the\nmap regardless of the map\u0027s frozen state.\n\nThis leads to a TOCTOU bug where userspace can call\nBPF_OBJ_GET_INFO_BY_FD to cache the hash and then modify the map\ncontents before freezing.\n\nTherefore, a trusted loader can be tricked into verifying the stale hash\nwhile loading the modified contents.\n\nFix this by returning -EPERM if the map is not frozen when the hash is\nrequested. This ensures the hash is only generated for the final,\nimmutable state of the map."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-27T12:17:46.284Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/7752d36343862323bbeea4ce3adf0ec2ed86e122"
        },
        {
          "url": "https://git.kernel.org/stable/c/f415e114b58fe02c41191e47f24bdabb438daf72"
        },
        {
          "url": "https://git.kernel.org/stable/c/a2c86aa621c22f2a7e26c654f936d65cfff0aa91"
        }
      ],
      "title": "bpf: Require frozen map for calculating map hash",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-45927",
    "datePublished": "2026-05-27T12:17:46.284Z",
    "dateReserved": "2026-05-13T15:03:33.086Z",
    "dateUpdated": "2026-05-27T12:17:46.284Z",
    "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.

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FKIE_CVE-2026-45927

CVE-2026-45927 (GCVE-0-2026-45927)

Tags

Sightings

Nomenclature