Vulnerability-Lookup

ubuntu-cve-2026-84963

Vulnerability from osv_ubuntu

Published

2026-09-03 16:18

Modified

2026-09-16 11:43

Summary

Details

An incorrect numeric conversion in the JSON parsing component of the MongoDB C Driver's BSON library may cause an unusually large text value to be silently shortened, or the corresponding field to be omitted, while the parsing operation still reports success and returns no error. An unauthenticated party who can supply the input processed by an application that uses this component may cause that application to hold data that does not match what was submitted, which may result in unintended alteration of data.

Severity

5.3 (Medium)


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

6.3 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-84963	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-84963	REPORT
	https://jira.mongodb.org/browse/CDRIVER-6407	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libbson-1.0-0",
            "binary_version": "1.16.1-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "libmongoc-1.0-0",
            "binary_version": "1.16.1-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "mongo-c-driver",
        "purl": "pkg:deb/ubuntu/mongo-c-driver@1.16.1-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.15.0-1",
        "1.15.1-1",
        "1.15.2-1",
        "1.16.0-1",
        "1.16.1-1",
        "1.16.1-1build1",
        "1.16.1-1build2",
        "1.16.1-1ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libbson-1.0-0",
            "binary_version": "1.21.0-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "libmongoc-1.0-0",
            "binary_version": "1.21.0-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "mongo-c-driver",
        "purl": "pkg:deb/ubuntu/mongo-c-driver@1.21.0-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.18.0-1",
        "1.19.1-1",
        "1.19.2-1",
        "1.20.0-1",
        "1.20.0-1build1",
        "1.20.1-1",
        "1.21.0-1",
        "1.21.0-1build1",
        "1.21.0-1ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libbson-1.0-0t64",
            "binary_version": "1.26.0-1.1ubuntu2+esm1"
          },
          {
            "binary_name": "libmongoc-1.0-0t64",
            "binary_version": "1.26.0-1.1ubuntu2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "mongo-c-driver",
        "purl": "pkg:deb/ubuntu/mongo-c-driver@1.26.0-1.1ubuntu2+esm1?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.24.3-1",
        "1.24.4-1",
        "1.25.1-1",
        "1.25.2-1",
        "1.25.4-1",
        "1.26.0-1",
        "1.26.0-1.1ubuntu1",
        "1.26.0-1.1ubuntu2",
        "1.26.0-1.1ubuntu2+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libbson2-2",
            "binary_version": "2.2.2-1"
          },
          {
            "binary_name": "libmongoc2-2",
            "binary_version": "2.2.2-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "mongo-c-driver",
        "purl": "pkg:deb/ubuntu/mongo-c-driver@2.2.2-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.30.4-1ubuntu1",
        "2.2.0-1",
        "2.2.1-1",
        "2.2.2-1"
      ]
    }
  ],
  "aliases": [],
  "details": "An incorrect numeric conversion in the JSON parsing component of the MongoDB C Driver\u0027s BSON library may cause an unusually large text value to be silently shortened, or the corresponding field to be omitted, while the parsing operation still reports success and returns no error. An unauthenticated party who can supply the input processed by an application that uses this component may cause that application to hold data that does not match what was submitted, which may result in unintended alteration of data.",
  "id": "UBUNTU-CVE-2026-84963",
  "modified": "2026-09-16T11:43:10Z",
  "published": "2026-09-03T16:18:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-84963"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-84963"
    },
    {
      "type": "REPORT",
      "url": "https://jira.mongodb.org/browse/CDRIVER-6407"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-84963"
  ]
}

CVE-2026-84963 (GCVE-0-2026-84963)

Vulnerability from cvelistv5 – Published: 2026-09-03 15:03 – Updated: 2026-09-03 15:35

Title

Silent field truncation via unchecked int cast of huge JSON string values in JSON-to-BSON parser

Summary

Severity

6.3 (Medium)


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

5.3 (Medium)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-03 15:35 UTC

CWE

CWE-681 - Incorrect Conversion between Numeric Types

Assigner

mongodb mitre root

References

1 reference

URL	Tags
https://jira.mongodb.org/browse/CDRIVER-6407

Impacted products

1 product

Vendor	Product	Version
MongoDB	C Driver	Affected: 1.10.0 , < 1.30.9 (semver) Affected: 2.0.0 , < 2.5.2 (semver)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-84963",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-03T15:35:10.846682Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
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    "cna": {
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          "product": "C Driver",
          "vendor": "MongoDB",
          "versions": [
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              "status": "affected",
              "version": "1.10.0",
              "versionType": "semver"
            },
            {
              "lessThan": "2.5.2",
              "status": "affected",
              "version": "2.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "An incorrect numeric conversion in the JSON parsing component of the MongoDB C Driver\u0027s BSON library may cause an unusually large text value to be silently shortened, or the corresponding field to be omitted, while the parsing operation still reports success and returns no error. An unauthenticated party who can supply the input processed by an application that uses this component may cause that application to hold data that does not match what was submitted, which may result in unintended alteration of data."
            }
          ],
          "value": "An incorrect numeric conversion in the JSON parsing component of the MongoDB C Driver\u0027s BSON library may cause an unusually large text value to be silently shortened, or the corresponding field to be omitted, while the parsing operation still reports success and returns no error. An unauthenticated party who can supply the input processed by an application that uses this component may cause that application to hold data that does not match what was submitted, which may result in unintended alteration of data."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
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            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
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            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "LOW",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
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            "version": "3.1"
          },
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          "scenarios": [
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      "problemTypes": [
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          "descriptions": [
            {
              "cweId": "CWE-681",
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      ],
      "providerMetadata": {
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        "orgId": "a39b4221-9bd0-4244-95fc-f3e2e07f1deb",
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      },
      "references": [
        {
          "url": "https://jira.mongodb.org/browse/CDRIVER-6407"
        }
      ],
      "source": {
        "discovery": "INTERNAL"
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      "title": "Silent field truncation via unchecked int cast of huge JSON string values in JSON-to-BSON parser",
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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.

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.