Vulnerability-Lookup

GCVE-1988-2026-0442

Vulnerability from gna-1988 – Published: 2026-11-02 07:29 – Updated: 2026-11-02 07:29

Title

[Bugtraq] CVE-2026-72711: Lean 4 kernel soundness bug — inference cache poisoning via opaque declarations (0 = 1 demonstrated)

Summary

1. Summary ========== A soundness bug in the Lean 4 kernel allows construction of a checked proof of False — and by extension, any proposition, including 0 = 1 — without axioms, sorry, unsafeCast, debug.skipKernelTC, or modified .olean files. The proof passes the kernel at maximum checking (--trust=0). The kernel's add_opaque path skips the closure check (check_no_metavar_no_fvar) that the definition and theorem paths perform. A stale entry in the type checker's inference cache can be reused after its local variable is gone, allowing a metaprogram to submit an opaque declaration whose value references an unbound free variable. The kernel then admits an opaque constant of type False. 2. Context ========== Lean 4 is increasingly used as a foundation for formally verified software, proof-carrying code, and mathematical libraries. Its kernel is the trusted core: every theorem must pass kernel type-checking before it is accepted. A soundness bug in the kernel undermines the guarantees of any system built on top of it. Formally verified systems certified under Common Criteria (ISO 15408) or DO-178C (airborne software) derive their assurance from the correctness of the proof checker. A kernel-level bypass invalidates that assurance chain. Independent checkers such as Nanoda and lean4lean that replay proofs against the same kernel rules are equally affected by the missing closure check. 3. Impact ========= - Formally verified software: any proposition can be "proved" and kernel-checked, including safety properties of compilers, OS kernels, and cryptographic libraries. - Proof-carrying code: a malicious Lake dependency could inject unsound opaque declarations that pass kernel checking. - Mathematical proof verification: results checked by the Lean kernel cannot be trusted on affected versions. 4. Proof of Concept =================== A Docker-reproducible PoC is available: git clone https://github.com/endrazine/lean-cve-poc-14484 cd lean-cve-poc-14484 docker build -t lean-cve-poc-14484 . docker run --rm lean-cve-poc-14484 On a vulnerable version, the output reports the proof of 0 = 1 as axiom-free. On a patched version, the kernel rejects the opaque declaration. 5. Root Cause ============= The function environment::add_opaque does not call check_no_metavar_no_fvar on the declaration's body, unlike the definition and theorem paths. This means: (a) A free variable (fvar) that existed in a now-discarded local context is not detected. CWE-488 (Exposure of Data Element to Wrong Session). (b) The kernel accepts a body containing references to variables that are no longer in scope. CWE-20 (Improper Input Validation). A metaprogram exploits this by caching a type-checking result for False against a temporary local, restoring the context, and submitting an opaque declaration referencing the stale cache entry. 6. Scoring ========== CVSS 3.1: AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N — 7.1 (High) CVSS 4.0: AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N — 6.8 (Medium) 7. CWE ====== CWE-488: Exposure of Data Element to Wrong Session CWE-20: Improper Input Validation 8. CVE ====== CVE-2026-72711 (assigned by VulnCheck as CNA) 9. Affected Versions ==================== Lean 4 < v4.32.2 (all versions from initial release) Fixed in: v4.32.2, v4.33.0, nightly 2026-07-23 and later 10. Mitigation ============== - Upgrade to Lean 4 v4.32.2 or later. - No workaround exists for affected versions — the flaw is in the kernel itself. 11. References ============== Bug report: https://github.com/leanprover/lean4/issues/14484 Fix: https://github.com/leanprover/lean4/pull/14498 PoC: https://github.com/endrazine/lean-cve-poc-14484 VulnCheck: https://www.vulncheck.com/advisories/lean-4-before-kernel-accepts-opaque-dec... NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72711 12. Timeline ============ 2026 Bug reported (leanprover/lean4#14484) 2026 Kernel fix merged (PR #14498) 2026-08-24 CVE-2026-72711 published by VulnCheck 2026-08-24 Docker-reproducible PoC published 13. Credit ========== Bug discovery: Patrick Hulin Kernel fix: Joachim Breitner (PR #14498) PoC packaging: Jonathan Brossard (@endrazine) — MOABI / PSIRT.com

Severity

No CVSS data available.

CWE

Assigner

VULNARCHIVE GNA GNA-1988

GNA scorecard E 38/100 over 556 records in the last 180 days details

References

7 references

URL	Tags
https://vuln.freearchive.org/archive/item/7b0ccc0…	technical-descriptionexploit
https://lists.securityfocus.com/hyperkitty/list/b…	technical-description
https://github.com/endrazine/lean-cve-poc-14484
https://github.com/leanprover/lean4/issues/14484
https://github.com/leanprover/lean4/pull/14498
https://nvd.nist.gov/vuln/detail/CVE-2026-72711
https://www.vulncheck.com/advisories/lean-4-befor…

Impacted products

1 product

Vendor	Product	Version	CPE status
leanprover	lean4	Affected: unknown	guessed

Credits

Jonathan Brossard

Relationships

analysis GCVE-1988-2026-0442 (this record)

related CVE-2026-72711

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "lean4",
          "vendor": "leanprover",
          "versions": [
            {
              "status": "affected",
              "version": "unknown"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Jonathan Brossard"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "1. Summary\n==========\nA soundness bug in the Lean 4 kernel allows construction of a checked\nproof of False \u2014 and by extension, any proposition, including 0 = 1 \u2014\nwithout axioms, sorry, unsafeCast, debug.skipKernelTC, or modified\n.olean files. The proof passes the kernel at maximum checking (--trust=0).\nThe kernel\u0027s add_opaque path skips the closure check\n(check_no_metavar_no_fvar) that the definition and theorem paths\nperform. A stale entry in the type checker\u0027s inference cache can be\nreused after its local variable is gone, allowing a metaprogram to\nsubmit an opaque declaration whose value references an unbound free\nvariable. The kernel then admits an opaque constant of type False.\n2. Context\n==========\nLean 4 is increasingly used as a foundation for formally verified\nsoftware, proof-carrying code, and mathematical libraries. Its kernel is\nthe trusted core: every theorem must pass kernel type-checking before it\nis accepted. A soundness bug in the kernel undermines the guarantees of\nany system built on top of it.\nFormally verified systems certified under Common Criteria (ISO 15408) or\nDO-178C (airborne software) derive their assurance from the correctness\nof the proof checker. A kernel-level bypass invalidates that assurance\nchain.\nIndependent checkers such as Nanoda and lean4lean that replay proofs\nagainst the same kernel rules are equally affected by the missing\nclosure check.\n3. Impact\n=========\n- Formally verified software: any proposition can be \"proved\" and\nkernel-checked, including safety properties of compilers, OS kernels,\nand cryptographic libraries.\n- Proof-carrying code: a malicious Lake dependency could inject unsound\nopaque declarations that pass kernel checking.\n- Mathematical proof verification: results checked by the Lean kernel\ncannot be trusted on affected versions.\n4. Proof of Concept\n===================\nA Docker-reproducible PoC is available:\ngit clone https://github.com/endrazine/lean-cve-poc-14484\ncd lean-cve-poc-14484\ndocker build -t lean-cve-poc-14484 .\ndocker run --rm lean-cve-poc-14484\nOn a vulnerable version, the output reports the proof of 0 = 1 as\naxiom-free. On a patched version, the kernel rejects the opaque\ndeclaration.\n5. Root Cause\n=============\nThe function environment::add_opaque does not call\ncheck_no_metavar_no_fvar on the declaration\u0027s body, unlike the\ndefinition and theorem paths. This means:\n(a) A free variable (fvar) that existed in a now-discarded local context\nis not detected. CWE-488 (Exposure of Data Element to Wrong Session).\n(b) The kernel accepts a body containing references to variables that\nare no longer in scope. CWE-20 (Improper Input Validation).\nA metaprogram exploits this by caching a type-checking result for False\nagainst a temporary local, restoring the context, and submitting an\nopaque declaration referencing the stale cache entry.\n6. Scoring\n==========\nCVSS 3.1: AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N \u2014 7.1 (High)\nCVSS 4.0: AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N \u2014 6.8\n(Medium)\n7. CWE\n======\nCWE-488: Exposure of Data Element to Wrong Session\nCWE-20: Improper Input Validation\n8. CVE\n======\nCVE-2026-72711 (assigned by VulnCheck as CNA)\n9. Affected Versions\n====================\nLean 4 \u003c v4.32.2 (all versions from initial release)\nFixed in: v4.32.2, v4.33.0, nightly 2026-07-23 and later\n10. Mitigation\n==============\n- Upgrade to Lean 4 v4.32.2 or later.\n- No workaround exists for affected versions \u2014 the flaw is in the\nkernel itself.\n11. References\n==============\nBug report:  https://github.com/leanprover/lean4/issues/14484\nFix:         https://github.com/leanprover/lean4/pull/14498\nPoC:         https://github.com/endrazine/lean-cve-poc-14484\nVulnCheck:\nhttps://www.vulncheck.com/advisories/lean-4-before-kernel-accepts-opaque-dec...\nNVD:         https://nvd.nist.gov/vuln/detail/CVE-2026-72711\n12. Timeline\n============\n2026        Bug reported (leanprover/lean4#14484)\n2026        Kernel fix merged (PR #14498)\n2026-08-24  CVE-2026-72711 published by VulnCheck\n2026-08-24  Docker-reproducible PoC published\n13. Credit\n==========\nBug discovery:   Patrick Hulin\nKernel fix:      Joachim Breitner (PR #14498)\nPoC packaging:   Jonathan Brossard (@endrazine) \u2014 MOABI / PSIRT.com"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-20",
              "description": "CWE-20",
              "lang": "en",
              "type": "CWE"
            },
            {
              "cweId": "CWE-488",
              "description": "CWE-488",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-11-02T07:29:44Z",
        "orgId": "4e2abfbf-4a2a-4b76-a4e0-d77c18ba156c",
        "shortName": "VULNARCHIVE"
      },
      "references": [
        {
          "tags": [
            "technical-description",
            "exploit"
          ],
          "url": "https://vuln.freearchive.org/archive/item/7b0ccc01e25fddbcaeadf955c7c62d194d45d1670b03c1a293a09d87a10cbc86"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://lists.securityfocus.com/hyperkitty/list/bugtraq@bugtraq.ai/message/HASOMMUIF672Y7I6NSEVO64G6IOOELJW/"
        },
        {
          "url": "https://github.com/endrazine/lean-cve-poc-14484"
        },
        {
          "url": "https://github.com/leanprover/lean4/issues/14484"
        },
        {
          "url": "https://github.com/leanprover/lean4/pull/14498"
        },
        {
          "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72711"
        },
        {
          "url": "https://www.vulncheck.com/advisories/lean-4-before-kernel-accepts-opaque-declaration-with-an-unbound-free-variable"
        }
      ],
      "source": {
        "defect": [
          "c7290a16-635f-49be-96f8-3b83b3ca52c7%40gmail.com"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "[Bugtraq] CVE-2026-72711: Lean 4 kernel soundness bug \u2014 inference cache poisoning via opaque declarations (0 = 1 demonstrated)",
      "x_gcve": [
        {
          "recordType": "analysis",
          "relationships": [
            {
              "destId": "CVE-2026-72711",
              "type": "related"
            }
          ],
          "vulnId": "GCVE-1988-2026-0442",
          "x_vulnarchive": {
            "archiveUrl": "https://vuln.freearchive.org/archive/item/7b0ccc01e25fddbcaeadf955c7c62d194d45d1670b03c1a293a09d87a10cbc86",
            "automated": true,
            "contentSha256": "7b0ccc01e25fddbcaeadf955c7c62d194d45d1670b03c1a293a09d87a10cbc86",
            "evidenceScore": 10,
            "messageId": "c7290a16-635f-49be-96f8-3b83b3ca52c7%40gmail.com",
            "originalUrl": "https://lists.securityfocus.com/hyperkitty/list/bugtraq@bugtraq.ai/message/HASOMMUIF672Y7I6NSEVO64G6IOOELJW/",
            "policy": "vulnarchive-1",
            "sourceFormat": "text/html",
            "sourcePublishedAt": "2026-11-02T07:29:44Z"
          }
        },
        {
          "recordType": "advisory",
          "vulnId": "gcve-1988-2026-0442"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "4e2abfbf-4a2a-4b76-a4e0-d77c18ba156c",
    "assignerShortName": "VULNARCHIVE",
    "datePublished": "2026-11-02T07:29:44Z",
    "dateUpdated": "2026-11-02T07:29:44Z",
    "state": "PUBLISHED",
    "vulnId": "GCVE-1988-2026-0442"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-72711 (GCVE-0-2026-72711)

Vulnerability from cvelistv5 – Published: 2026-08-24 20:08 – Updated: 2026-10-26 01:23

Title

Lean 4 before 4.32.2 Kernel Accepts Opaque Declaration With an Unbound Free Variable

Summary

The Lean 4 kernel does not check that the body of an opaque declaration is closed. environment::add_opaque omits the check_no_metavar_no_fvar call that the definition and theorem paths perform, so a value containing a free variable that is absent from the local context is not rejected outright. A metaprogram can first cause the kernel to create a temporary local of type False and record its type in the type checker's inference cache, then restore the local context while that cache entry persists on the same type checker instance, and finally submit an opaque declaration whose value is the now-unbound variable. The cache lookup answers before the branch that would test membership of the local context, so the kernel infers the cached type and admits an opaque constant of type False, from which any proposition follows. The declaration is accepted through the ordinary checked path at maximum kernel checking, without sorry, unsafeCast, debug.skipKernelTC, addDeclWithoutChecking, foreign code or a modified .olean file, and the result carries no axioms. Fixed in 4.32.2 by adding the missing closure check.

Severity

6.8 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

6.3 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-24 20:14 UTC

CWE

CWE-20 - Improper Input Validation

Assigner

VulnCheck CNA under the mitre root

CNA scorecard B 84/100 over 7611 records in the last 180 days details

References

6 references

URL	Tags
https://github.com/leanprover/lean4	product
https://github.com/leanprover/lean4/issues/14484	issue-tracking
https://github.com/leanprover/lean4/pull/14498	issue-trackingpatch
https://github.com/endrazine/lean-cve-poc-14484	exploit
https://www.vulncheck.com/advisories/lean-4-befor…	third-party-advisory
http://www.openwall.com/lists/oss-security/2026/10/26/3

Impacted products

1 product

Vendor	Product	Version
leanprover	lean4	Affected: 0 , < 4.32.2 (semver)

Date Public

2026-07-22 00:00

Credits

Patrick Hulin Jonathan Brossard (MOABI)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-72711",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-24T20:14:31.474084Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-24T20:14:41.969Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2026-10-26T01:23:57.370Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/10/26/3"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:github/leanprover/lean4",
          "product": "lean4",
          "repo": "https://github.com/leanprover/lean4",
          "vendor": "leanprover",
          "versions": [
            {
              "lessThan": "4.32.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Patrick Hulin"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Jonathan Brossard (MOABI)"
        }
      ],
      "datePublic": "2026-07-22T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "The Lean 4 kernel does not check that the body of an opaque declaration is closed. environment::add_opaque omits the check_no_metavar_no_fvar call that the definition and theorem paths perform, so a value containing a free variable that is absent from the local context is not rejected outright. A metaprogram can first cause the kernel to create a temporary local of type False and record its type in the type checker\u0027s inference cache, then restore the local context while that cache entry persists on the same type checker instance, and finally submit an opaque declaration whose value is the now-unbound variable. The cache lookup answers before the branch that would test membership of the local context, so the kernel infers the cached type and admits an opaque constant of type False, from which any proposition follows. The declaration is accepted through the ordinary checked path at maximum kernel checking, without sorry, unsafeCast, debug.skipKernelTC, addDeclWithoutChecking, foreign code or a modified .olean file, and the result carries no axioms. Fixed in 4.32.2 by adding the missing closure check."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "NONE",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-20",
              "description": "Improper Input Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-24T14:18:53.683Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/leanprover/lean4"
        },
        {
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/leanprover/lean4/issues/14484"
        },
        {
          "tags": [
            "issue-tracking",
            "patch"
          ],
          "url": "https://github.com/leanprover/lean4/pull/14498"
        },
        {
          "tags": [
            "exploit"
          ],
          "url": "https://github.com/endrazine/lean-cve-poc-14484"
        },
        {
          "name": "VulnCheck Advisory: Lean 4 before 4.32.2 Kernel Accepts Opaque Declaration With an Unbound Free Variable",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/lean-4-before-kernel-accepts-opaque-declaration-with-an-unbound-free-variable"
        }
      ],
      "title": "Lean 4 before 4.32.2 Kernel Accepts Opaque Declaration With an Unbound Free Variable",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-72711",
    "datePublished": "2026-08-24T20:08:33.219Z",
    "dateReserved": "2026-08-10T13:02:52.001Z",
    "dateUpdated": "2026-10-26T01:23:57.370Z",
    "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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

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