GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2021-29953 (GCVE-0-2021-29953)

Vulnerability from cvelistv5 – Published: 2021-06-24 13:17 – Updated: 2024-08-03 22:18
VLAI
Summary
A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox < 88.0.1 and Firefox for Android < 88.1.3.
CWE
  • Universal Cross-Site Scripting
References
Impacted products
Vendor Product Version CPE status
Mozilla Firefox Affected: unspecified , < 88.0.1 (custom)
guessed Create a notification for this product.
Mozilla Firefox for Android Affected: unspecified , < 88.1.3 (custom)
guessed Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T22:18:03.472Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://www.mozilla.org/security/advisories/mfsa2021-20/"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1701684"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThan": "88.0.1",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        },
        {
          "product": "Firefox for Android",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThan": "88.1.3",
              "status": "affected",
              "version": "unspecified",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox \u003c 88.0.1 and Firefox for Android \u003c 88.1.3."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "Universal Cross-Site Scripting",
              "lang": "en",
              "type": "text"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2021-06-24T13:17:57.000Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://www.mozilla.org/security/advisories/mfsa2021-20/"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1701684"
        }
      ],
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security@mozilla.org",
          "ID": "CVE-2021-29953",
          "STATE": "PUBLIC"
        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "Firefox",
                      "version": {
                        "version_data": [
                          {
                            "version_affected": "\u003c",
                            "version_value": "88.0.1"
                          }
                        ]
                      }
                    },
                    {
                      "product_name": "Firefox for Android",
                      "version": {
                        "version_data": [
                          {
                            "version_affected": "\u003c",
                            "version_value": "88.1.3"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "Mozilla"
              }
            ]
          }
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "eng",
              "value": "A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox \u003c 88.0.1 and Firefox for Android \u003c 88.1.3."
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "eng",
                  "value": "Universal Cross-Site Scripting"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://www.mozilla.org/security/advisories/mfsa2021-20/",
              "refsource": "MISC",
              "url": "https://www.mozilla.org/security/advisories/mfsa2021-20/"
            },
            {
              "name": "https://bugzilla.mozilla.org/show_bug.cgi?id=1701684",
              "refsource": "MISC",
              "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1701684"
            }
          ]
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2021-29953",
    "datePublished": "2021-06-24T13:17:57.000Z",
    "dateReserved": "2021-04-01T00:00:00.000Z",
    "dateUpdated": "2024-08-03T22:18:03.472Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2021-29953",
      "date": "2026-09-16",
      "epss": "0.00647",
      "percentile": "0.49327"
    },
    "fkie_nvd": {
      "configurations": "[{\"nodes\": [{\"operator\": \"OR\", \"negate\": false, \"cpeMatch\": [{\"vulnerable\": true, \"criteria\": \"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:-:*:*\", \"versionEndExcluding\": \"88.0.1\", \"matchCriteriaId\": \"9DA518B8-6A0A-4AD2-A4C9-6FF6AEA7B56F\"}, {\"vulnerable\": true, \"criteria\": \"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:android:*:*\", \"versionEndExcluding\": \"88.1.3\", \"matchCriteriaId\": \"1399E175-84F3-424E-8B02-FAF944DA1D84\"}]}]}]",
      "descriptions": "[{\"lang\": \"en\", \"value\": \"A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox \u003c 88.0.1 and Firefox for Android \u003c 88.1.3.\"}, {\"lang\": \"es\", \"value\": \"Una p\\u00e1gina web maliciosa podr\\u00eda haber forzado a un usuario de Firefox para Android a ejecutar JavaScript controlado por el atacante en el contexto de otro dominio, resultando en una vulnerabilidad de tipo Universal Cross-Site Scripting . *Nota: Este problema s\\u00f3lo afecta a Firefox para Android. Otros sistemas operativos no est\\u00e1n afectados. Se est\\u00e1n reteniendo temporalmente m\\u00e1s detalles para dar a usuarios la oportunidad de actualizarse. Esta vulnerabilidad afecta a Firefox versiones anteriores a 88.0.1 y a Firefox para Android versiones anteriores a 88.1.3\"}]",
      "id": "CVE-2021-29953",
      "lastModified": "2024-11-21T06:02:03.037",
      "metrics": "{\"cvssMetricV31\": [{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"3.1\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N\", \"baseScore\": 6.1, \"baseSeverity\": \"MEDIUM\", \"attackVector\": \"NETWORK\", \"attackComplexity\": \"LOW\", \"privilegesRequired\": \"NONE\", \"userInteraction\": \"REQUIRED\", \"scope\": \"CHANGED\", \"confidentialityImpact\": \"LOW\", \"integrityImpact\": \"LOW\", \"availabilityImpact\": \"NONE\"}, \"exploitabilityScore\": 2.8, \"impactScore\": 2.7}], \"cvssMetricV2\": [{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"2.0\", \"vectorString\": \"AV:N/AC:M/Au:N/C:N/I:P/A:N\", \"baseScore\": 4.3, \"accessVector\": \"NETWORK\", \"accessComplexity\": \"MEDIUM\", \"authentication\": \"NONE\", \"confidentialityImpact\": \"NONE\", \"integrityImpact\": \"PARTIAL\", \"availabilityImpact\": \"NONE\"}, \"baseSeverity\": \"MEDIUM\", \"exploitabilityScore\": 8.6, \"impactScore\": 2.9, \"acInsufInfo\": false, \"obtainAllPrivilege\": false, \"obtainUserPrivilege\": false, \"obtainOtherPrivilege\": false, \"userInteractionRequired\": true}]}",
      "published": "2021-06-24T14:15:10.000",
      "references": "[{\"url\": \"https://bugzilla.mozilla.org/show_bug.cgi?id=1701684\", \"source\": \"security@mozilla.org\", \"tags\": [\"Permissions Required\", \"Vendor Advisory\"]}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2021-20/\", \"source\": \"security@mozilla.org\", \"tags\": [\"Release Notes\", \"Vendor Advisory\"]}, {\"url\": \"https://bugzilla.mozilla.org/show_bug.cgi?id=1701684\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Permissions Required\", \"Vendor Advisory\"]}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2021-20/\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Release Notes\", \"Vendor Advisory\"]}]",
      "sourceIdentifier": "security@mozilla.org",
      "vulnStatus": "Modified",
      "weaknesses": "[{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"description\": [{\"lang\": \"en\", \"value\": \"CWE-79\"}]}]"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2021-29953\",\"sourceIdentifier\":\"security@mozilla.org\",\"published\":\"2021-06-24T14:15:10.000\",\"lastModified\":\"2024-11-21T06:02:03.037\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox \u003c 88.0.1 and Firefox for Android \u003c 88.1.3.\"},{\"lang\":\"es\",\"value\":\"Una p\u00e1gina web maliciosa podr\u00eda haber forzado a un usuario de Firefox para Android a ejecutar JavaScript controlado por el atacante en el contexto de otro dominio, resultando en una vulnerabilidad de tipo Universal Cross-Site Scripting . *Nota: Este problema s\u00f3lo afecta a Firefox para Android. Otros sistemas operativos no est\u00e1n afectados. Se est\u00e1n reteniendo temporalmente m\u00e1s detalles para dar a usuarios la oportunidad de actualizarse. Esta vulnerabilidad afecta a Firefox versiones anteriores a 88.0.1 y a Firefox para Android versiones anteriores a 88.1.3\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N\",\"baseScore\":6.1,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"CHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"LOW\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":2.8,\"impactScore\":2.7}],\"cvssMetricV2\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"2.0\",\"vectorString\":\"AV:N/AC:M/Au:N/C:N/I:P/A:N\",\"baseScore\":4.3,\"accessVector\":\"NETWORK\",\"accessComplexity\":\"MEDIUM\",\"authentication\":\"NONE\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"PARTIAL\",\"availabilityImpact\":\"NONE\"},\"baseSeverity\":\"MEDIUM\",\"exploitabilityScore\":8.6,\"impactScore\":2.9,\"acInsufInfo\":false,\"obtainAllPrivilege\":false,\"obtainUserPrivilege\":false,\"obtainOtherPrivilege\":false,\"userInteractionRequired\":true}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-79\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:-:*:*\",\"versionEndExcluding\":\"88.0.1\",\"matchCriteriaId\":\"9DA518B8-6A0A-4AD2-A4C9-6FF6AEA7B56F\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:android:*:*\",\"versionEndExcluding\":\"88.1.3\",\"matchCriteriaId\":\"1399E175-84F3-424E-8B02-FAF944DA1D84\"}]}]}],\"references\":[{\"url\":\"https://bugzilla.mozilla.org/show_bug.cgi?id=1701684\",\"source\":\"security@mozilla.org\",\"tags\":[\"Permissions Required\",\"Vendor Advisory\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2021-20/\",\"source\":\"security@mozilla.org\",\"tags\":[\"Release Notes\",\"Vendor Advisory\"]},{\"url\":\"https://bugzilla.mozilla.org/show_bug.cgi?id=1701684\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Permissions Required\",\"Vendor Advisory\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2021-20/\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Release Notes\",\"Vendor Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Critical",
      "current_release_date": "2025-11-21T16:12:27+00:00",
      "cve": "CVE-2021-29953",
      "id": "CVE-2021-29953",
      "initial_release_date": "2021-05-05T00:00:00+00:00",
      "product_status:known_not_affected": "6",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "Mozilla: Universal Cross-Site Scripting",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-29953.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

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.


Loading…