Vulnerability-Lookup

GHSA-Q637-VRQ8-P3JV

Vulnerability from github – Published: 2026-05-08 15:31 – Updated: 2026-05-15 21:31

Details

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

bpf: crypto: Use the correct destructor kfunc type

With CONFIG_CFI enabled, the kernel strictly enforces that indirect function calls use a function pointer type that matches the target function. I ran into the following type mismatch when running BPF self-tests:

CFI failure at bpf_obj_free_fields+0x190/0x238 (target: bpf_crypto_ctx_release+0x0/0x94; expected type: 0xa488ebfc) Internal error: Oops - CFI: 00000000f2008228 [#1] SMP ...

As bpf_crypto_ctx_release() is also used in BPF programs and using a void pointer as the argument would make the verifier unhappy, add a simple stub function with the correct type and register it as the destructor kfunc instead.

Severity

5.5 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-43306"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-08T14:16:37Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: crypto: Use the correct destructor kfunc type\n\nWith CONFIG_CFI enabled, the kernel strictly enforces that indirect\nfunction calls use a function pointer type that matches the target\nfunction. I ran into the following type mismatch when running BPF\nself-tests:\n\n  CFI failure at bpf_obj_free_fields+0x190/0x238 (target:\n    bpf_crypto_ctx_release+0x0/0x94; expected type: 0xa488ebfc)\n  Internal error: Oops - CFI: 00000000f2008228 [#1]  SMP\n  ...\n\nAs bpf_crypto_ctx_release() is also used in BPF programs and using\na void pointer as the argument would make the verifier unhappy, add\na simple stub function with the correct type and register it as the\ndestructor kfunc instead.",
  "id": "GHSA-q637-vrq8-p3jv",
  "modified": "2026-05-15T21:31:30Z",
  "published": "2026-05-08T15:31:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-43306"
    },
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    },
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      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4e3e57dbf46dad3498f8c4219ce2dba756875962"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/50d6fd69388cc7b05dce72f09080674dcede4ac9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b40a5d724f29fc2eed23ff353808a9aae616b48a"
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  "severity": [
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      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-43306 (GCVE-0-2026-43306)

Vulnerability from cvelistv5 – Published: 2026-05-08 13:11 – Updated: 2026-05-11 22:22

Title

bpf: crypto: Use the correct destructor kfunc type

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: crypto: Use the correct destructor kfunc type With CONFIG_CFI enabled, the kernel strictly enforces that indirect function calls use a function pointer type that matches the target function. I ran into the following type mismatch when running BPF self-tests: CFI failure at bpf_obj_free_fields+0x190/0x238 (target: bpf_crypto_ctx_release+0x0/0x94; expected type: 0xa488ebfc) Internal error: Oops - CFI: 00000000f2008228 [#1] SMP ... As bpf_crypto_ctx_release() is also used in BPF programs and using a void pointer as the argument would make the verifier unhappy, add a simple stub function with the correct type and register it as the destructor kfunc instead.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

4 references

URL	Tags
https://git.kernel.org/stable/c/4e3e57dbf46dad349…
https://git.kernel.org/stable/c/50d6fd69388cc7b05…
https://git.kernel.org/stable/c/3979a550fe06b370d…
https://git.kernel.org/stable/c/b40a5d724f29fc2ee…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 3e1c6f35409f9e447bf37f64840f5b65576bfb78 , < 4e3e57dbf46dad3498f8c4219ce2dba756875962 (git) Affected: 3e1c6f35409f9e447bf37f64840f5b65576bfb78 , < 50d6fd69388cc7b05dce72f09080674dcede4ac9 (git) Affected: 3e1c6f35409f9e447bf37f64840f5b65576bfb78 , < 3979a550fe06b370d73647f59cf462fa525c9ec4 (git) Affected: 3e1c6f35409f9e447bf37f64840f5b65576bfb78 , < b40a5d724f29fc2eed23ff353808a9aae616b48a (git)
Linux	Linux	Affected: 6.10 Unaffected: 0 , < 6.10 (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)

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JSON

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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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