Vulnerability-Lookup

FKIE_CVE-2026-39934

Vulnerability from fkie_nvd - Published: 2026-04-07 22:16 - Updated: 2026-07-21 19:10

Severity

6.9 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L

Summary

Loop with unreachable exit condition ('infinite loop') vulnerability in The Wikimedia Foundation Mediawiki - GrowthExperiments Extension allows Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions. This issue was remediated only on the `master` branch.

References

	URL	Tags
	c4f26cc8-17ff-4c99-b5e2-38fc1793eacc	https://gerrit.wikimedia.org/r/c/1243874
	c4f26cc8-17ff-4c99-b5e2-38fc1793eacc	https://phabricator.wikimedia.org/T418222

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "affected",
          "product": "Mediawiki - GrowthExperiments Extension",
          "vendor": "The Wikimedia Foundation",
          "versions": [
            {
              "status": "affected",
              "version": "1.45"
            },
            {
              "status": "affected",
              "version": "1.44"
            },
            {
              "status": "affected",
              "version": "1.43"
            },
            {
              "lessThan": "1.43",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Loop with unreachable exit condition (\u0027infinite loop\u0027) vulnerability in The Wikimedia Foundation Mediawiki - GrowthExperiments Extension allows Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions. This issue was remediated only on the `master` branch."
    },
    {
      "lang": "es",
      "value": "Vulnerabilidad de bucle con condici\u00f3n de salida inalcanzable (\u0027bucle infinito\u0027) en la Extensi\u00f3n Mediawiki - GrowthExperiments de The Wikimedia Foundation permite el aprovechamiento de condiciones de carrera de Tiempo de Verificaci\u00f3n y Tiempo de Uso (TOCTOU). Este problema afecta a la Extensi\u00f3n Mediawiki - GrowthExperiments: 1.45.2, 1.44.4, 1.43.7."
    }
  ],
  "id": "CVE-2026-39934",
  "lastModified": "2026-07-21T19:10:00.107",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 6.9,
          "baseSeverity": "MEDIUM",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "LOW",
          "subConfidentialityImpact": "LOW",
          "subIntegrityImpact": "LOW",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "LOW",
          "vulnConfidentialityImpact": "LOW",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-39934",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-04-08T15:20:23.112186Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-04-07T22:16:24.137",
  "references": [
    {
      "source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
      "url": "https://gerrit.wikimedia.org/r/c/1243874"
    },
    {
      "source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
      "url": "https://phabricator.wikimedia.org/T418222"
    }
  ],
  "sourceIdentifier": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-835"
        }
      ],
      "source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
      "type": "Secondary"
    }
  ]
}

CVE-2026-39934 (GCVE-0-2026-39934)

Vulnerability from cvelistv5 – Published: 2026-04-07 22:00 – Updated: 2026-04-08 22:04

Title

Growth Experiments ReassignMenteesJob runs as an infinite loop

Summary

Severity

6.9 (Medium)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-08 15:20 UTC

CWE

CWE-835 - Loop with unreachable exit condition ('infinite loop')

Assigner

wikimedia-foundation mitre root

References

2 references

URL	Tags
https://phabricator.wikimedia.org/T418222
https://gerrit.wikimedia.org/r/c/1243874

Impacted products

1 product

Vendor	Product	Version
The Wikimedia Foundation	Mediawiki - GrowthExperiments Extension	Affected: 1.45 Affected: 1.44 Affected: 1.43 Affected: 0 , < 1.43 (custom)

Credits

Urbanecm_WMF Michael

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-39934",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-08T15:20:23.112186Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-08T15:20:39.477Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "product": "Mediawiki - GrowthExperiments Extension",
          "vendor": "The Wikimedia Foundation",
          "versions": [
            {
              "status": "affected",
              "version": "1.45"
            },
            {
              "status": "affected",
              "version": "1.44"
            },
            {
              "status": "affected",
              "version": "1.43"
            },
            {
              "lessThan": "1.43",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Urbanecm_WMF"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Michael"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Loop with unreachable exit condition (\u0027infinite loop\u0027) vulnerability in The Wikimedia Foundation Mediawiki - GrowthExperiments Extension allows Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions. This issue was remediated only on the `master` branch."
            }
          ],
          "value": "Loop with unreachable exit condition (\u0027infinite loop\u0027) vulnerability in The Wikimedia Foundation Mediawiki - GrowthExperiments Extension allows Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions. This issue was remediated only on the `master` branch."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-29",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-29 Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 6.9,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "LOW",
            "subConfidentialityImpact": "LOW",
            "subIntegrityImpact": "LOW",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "LOW",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-835",
              "description": "CWE-835 Loop with unreachable exit condition (\u0027infinite loop\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-08T22:04:41.006Z",
        "orgId": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
        "shortName": "wikimedia-foundation"
      },
      "references": [
        {
          "url": "https://phabricator.wikimedia.org/T418222"
        },
        {
          "url": "https://gerrit.wikimedia.org/r/c/1243874"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Growth Experiments ReassignMenteesJob runs as an infinite loop",
      "x_generator": {
        "engine": "Vulnogram 1.0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
    "assignerShortName": "wikimedia-foundation",
    "cveId": "CVE-2026-39934",
    "datePublished": "2026-04-07T22:00:46.100Z",
    "dateReserved": "2026-04-07T21:25:36.589Z",
    "dateUpdated": "2026-04-08T22:04:41.006Z",
    "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.

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.