Vulnerability-Lookup

FKIE_CVE-2021-29945

Vulnerability from fkie_nvd - Published: 2021-06-24 14:15 - Updated: 2026-06-17 03:48

Severity

6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Summary

The WebAssembly JIT could miscalculate the size of a return type, which could lead to a null read and result in a crash. *Note: This issue only affected x86-32 platforms. Other platforms are unaffected.*. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

References

URL	Tags
security@mozilla.org	https://bugzilla.mozilla.org/show_bug.cgi?id=1700690	Issue Tracking, Permissions Required, Vendor Advisory
security@mozilla.org	https://www.mozilla.org/security/advisories/mfsa2021-14/	Release Notes, Vendor Advisory
security@mozilla.org	https://www.mozilla.org/security/advisories/mfsa2021-15/	Release Notes, Vendor Advisory
security@mozilla.org	https://www.mozilla.org/security/advisories/mfsa2021-16/	Release Notes, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	https://bugzilla.mozilla.org/show_bug.cgi?id=1700690	Issue Tracking, Permissions Required, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	https://www.mozilla.org/security/advisories/mfsa2021-14/	Release Notes, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	https://www.mozilla.org/security/advisories/mfsa2021-15/	Release Notes, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	https://www.mozilla.org/security/advisories/mfsa2021-16/	Release Notes, Vendor Advisory

Impacted products

Vendor	Product	Version
mozilla	firefox	*
mozilla	firefox_esr	*
mozilla	thunderbird	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Firefox ESR",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThan": "78.10",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThan": "78.10",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        },
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThan": "88",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "security@mozilla.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:x86:*",
              "matchCriteriaId": "93A024F9-E2A3-4F13-83A3-879EAC032592",
              "versionEndExcluding": "88.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:x86:*",
              "matchCriteriaId": "504327C0-E11F-4EAC-9ED3-8BEA4C40DD0C",
              "versionEndExcluding": "78.10",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:x86:*",
              "matchCriteriaId": "65A9C7EC-D89C-4C03-841E-9DFED53E5795",
              "versionEndExcluding": "78.10",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The WebAssembly JIT could miscalculate the size of a return type, which could lead to a null read and result in a crash. *Note: This issue only affected x86-32 platforms. Other platforms are unaffected.*. This vulnerability affects Firefox ESR \u003c 78.10, Thunderbird \u003c 78.10, and Firefox \u003c 88."
    },
    {
      "lang": "es",
      "value": "El JIT de WebAssembly pod\u00eda calcular mal el tama\u00f1o de un tipo de retorno, lo que pod\u00eda conllevar a una lectura nula y resultar en un bloqueo. *Nota: Este problema s\u00f3lo afectaba a las plataformas x86-32. Otras plataformas no est\u00e1n afectadas. Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 78.10, Thunderbird versiones anteriores a 78.10 y Firefox versiones anteriores a 88"
    }
  ],
  "id": "CVE-2021-29945",
  "lastModified": "2026-06-17T03:48:29.313",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 4.3,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:M/Au:N/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-06-24T14:15:09.763",
  "references": [
    {
      "source": "security@mozilla.org",
      "tags": [
        "Issue Tracking",
        "Permissions Required",
        "Vendor Advisory"
      ],
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1700690"
    },
    {
      "source": "security@mozilla.org",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2021-14/"
    },
    {
      "source": "security@mozilla.org",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2021-15/"
    },
    {
      "source": "security@mozilla.org",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2021-16/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Issue Tracking",
        "Permissions Required",
        "Vendor Advisory"
      ],
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1700690"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2021-14/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2021-15/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2021-16/"
    }
  ],
  "sourceIdentifier": "security@mozilla.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-682"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2021-29945 (GCVE-0-2021-29945)

Vulnerability from cvelistv5 – Published: 2021-06-24 13:19 – Updated: 2024-08-03 22:18

Summary

Severity

No CVSS data available.

CWE

Incorrect size computation in WebAssembly JIT could lead to null-reads

Assigner

mozilla mitre root

References

4 references

URL	Tags
https://www.mozilla.org/security/advisories/mfsa2…	x_refsource_MISC
https://www.mozilla.org/security/advisories/mfsa2…	x_refsource_MISC
https://www.mozilla.org/security/advisories/mfsa2…	x_refsource_MISC
https://bugzilla.mozilla.org/show_bug.cgi?id=1700690	x_refsource_MISC

Impacted products

3 products

Vendor	Product	Version
Mozilla	Firefox ESR	Affected: unspecified , < 78.10 (custom)
Mozilla	Thunderbird	Affected: unspecified , < 78.10 (custom)
Mozilla	Firefox	Affected: unspecified , < 88 (custom)

Show details on NVD website

JSON

To clipboard

{
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          "dateUpdated": "2024-08-03T22:18:03.472Z",
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            ],
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          },
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            ],
            "url": "https://www.mozilla.org/security/advisories/mfsa2021-16/"
          },
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            ],
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          },
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            ],
            "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1700690"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Firefox ESR",
          "vendor": "Mozilla",
          "versions": [
            {
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              "version": "unspecified",
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          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
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              "status": "affected",
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            }
          ]
        },
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      "problemTypes": [
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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.

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.

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FKIE_CVE-2021-29945

CVE-2021-29945 (GCVE-0-2021-29945)

Tags

Sightings

Nomenclature

Related by attack behaviour