CVE-2021-29946 (GCVE-0-2021-29946)

Vulnerability from cvelistv5 – Published: 2021-06-24 13:19 – Updated: 2024-08-03 22:18
VLAI
Summary
Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • Port blocking could be bypassed
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox ESR Affected: unspecified , < 78.10 (custom)
Create a notification for this product.
Mozilla Thunderbird Affected: unspecified , < 78.10 (custom)
Create a notification for this product.
Mozilla Firefox Affected: unspecified , < 88 (custom)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-03T22:18:03.473Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://www.mozilla.org/security/advisories/mfsa2021-14/"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://www.mozilla.org/security/advisories/mfsa2021-16/"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://www.mozilla.org/security/advisories/mfsa2021-15/"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1698503"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "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"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header. This vulnerability affects Firefox ESR \u003c 78.10, Thunderbird \u003c 78.10, and Firefox \u003c 88."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "Port blocking could be bypassed",
              "lang": "en",
              "type": "text"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2021-06-24T13:19:43.000Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://www.mozilla.org/security/advisories/mfsa2021-14/"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://www.mozilla.org/security/advisories/mfsa2021-16/"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://www.mozilla.org/security/advisories/mfsa2021-15/"
        },
        {
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1698503"
        }
      ],
      "x_legacyV4Record": {
        "CVE_data_meta": {
          "ASSIGNER": "security@mozilla.org",
          "ID": "CVE-2021-29946",
          "STATE": "PUBLIC"
        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "Firefox ESR",
                      "version": {
                        "version_data": [
                          {
                            "version_affected": "\u003c",
                            "version_value": "78.10"
                          }
                        ]
                      }
                    },
                    {
                      "product_name": "Thunderbird",
                      "version": {
                        "version_data": [
                          {
                            "version_affected": "\u003c",
                            "version_value": "78.10"
                          }
                        ]
                      }
                    },
                    {
                      "product_name": "Firefox",
                      "version": {
                        "version_data": [
                          {
                            "version_affected": "\u003c",
                            "version_value": "88"
                          }
                        ]
                      }
                    }
                  ]
                },
                "vendor_name": "Mozilla"
              }
            ]
          }
        },
        "data_format": "MITRE",
        "data_type": "CVE",
        "data_version": "4.0",
        "description": {
          "description_data": [
            {
              "lang": "eng",
              "value": "Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header. This vulnerability affects Firefox ESR \u003c 78.10, Thunderbird \u003c 78.10, and Firefox \u003c 88."
            }
          ]
        },
        "problemtype": {
          "problemtype_data": [
            {
              "description": [
                {
                  "lang": "eng",
                  "value": "Port blocking could be bypassed"
                }
              ]
            }
          ]
        },
        "references": {
          "reference_data": [
            {
              "name": "https://www.mozilla.org/security/advisories/mfsa2021-14/",
              "refsource": "MISC",
              "url": "https://www.mozilla.org/security/advisories/mfsa2021-14/"
            },
            {
              "name": "https://www.mozilla.org/security/advisories/mfsa2021-16/",
              "refsource": "MISC",
              "url": "https://www.mozilla.org/security/advisories/mfsa2021-16/"
            },
            {
              "name": "https://www.mozilla.org/security/advisories/mfsa2021-15/",
              "refsource": "MISC",
              "url": "https://www.mozilla.org/security/advisories/mfsa2021-15/"
            },
            {
              "name": "https://bugzilla.mozilla.org/show_bug.cgi?id=1698503",
              "refsource": "MISC",
              "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1698503"
            }
          ]
        }
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2021-29946",
    "datePublished": "2021-06-24T13:19:43.000Z",
    "dateReserved": "2021-04-01T00:00:00.000Z",
    "dateUpdated": "2024-08-03T22:18:03.473Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2021-29946",
      "date": "2026-07-15",
      "epss": "0.01167",
      "percentile": "0.63735"
    },
    "fkie_nvd": {
      "configurations": "[{\"nodes\": [{\"operator\": \"OR\", \"negate\": false, \"cpeMatch\": [{\"vulnerable\": true, \"criteria\": \"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*\", \"versionEndExcluding\": \"88.0\", \"matchCriteriaId\": \"05F82833-4C58-4D1A-B9FC-EDBE88FF93EA\"}, {\"vulnerable\": true, \"criteria\": \"cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*\", \"versionEndExcluding\": \"78.10\", \"matchCriteriaId\": \"88984706-ACE5-4873-AC24-9D1670EE94F5\"}, {\"vulnerable\": true, \"criteria\": \"cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*\", \"versionEndExcluding\": \"78.10\", \"matchCriteriaId\": \"362E8881-7A6C-400C-A128-BBA57710F340\"}]}]}]",
      "descriptions": "[{\"lang\": \"en\", \"value\": \"Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header. This vulnerability affects Firefox ESR \u003c 78.10, Thunderbird \u003c 78.10, and Firefox \u003c 88.\"}, {\"lang\": \"es\", \"value\": \"Los puertos que se escribieron como un desbordamiento de enteros por encima de los l\\u00edmites de un entero de 16 bits podr\\u00edan haber omitido las restricciones de bloqueo de puertos cuando se usaron en la cabecera Alt-Svc. 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-2021-29946",
      "lastModified": "2024-11-21T06:02:02.163",
      "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:U/C:H/I:H/A:H\", \"baseScore\": 8.8, \"baseSeverity\": \"HIGH\", \"attackVector\": \"NETWORK\", \"attackComplexity\": \"LOW\", \"privilegesRequired\": \"NONE\", \"userInteraction\": \"REQUIRED\", \"scope\": \"UNCHANGED\", \"confidentialityImpact\": \"HIGH\", \"integrityImpact\": \"HIGH\", \"availabilityImpact\": \"HIGH\"}, \"exploitabilityScore\": 2.8, \"impactScore\": 5.9}], \"cvssMetricV2\": [{\"source\": \"nvd@nist.gov\", \"type\": \"Primary\", \"cvssData\": {\"version\": \"2.0\", \"vectorString\": \"AV:N/AC:M/Au:N/C:P/I:P/A:P\", \"baseScore\": 6.8, \"accessVector\": \"NETWORK\", \"accessComplexity\": \"MEDIUM\", \"authentication\": \"NONE\", \"confidentialityImpact\": \"PARTIAL\", \"integrityImpact\": \"PARTIAL\", \"availabilityImpact\": \"PARTIAL\"}, \"baseSeverity\": \"MEDIUM\", \"exploitabilityScore\": 8.6, \"impactScore\": 6.4, \"acInsufInfo\": false, \"obtainAllPrivilege\": false, \"obtainUserPrivilege\": false, \"obtainOtherPrivilege\": false, \"userInteractionRequired\": true}]}",
      "published": "2021-06-24T14:15:09.797",
      "references": "[{\"url\": \"https://bugzilla.mozilla.org/show_bug.cgi?id=1698503\", \"source\": \"security@mozilla.org\", \"tags\": [\"Permissions Required\", \"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\": \"security@mozilla.org\", \"tags\": [\"Release Notes\", \"Vendor Advisory\"]}, {\"url\": \"https://bugzilla.mozilla.org/show_bug.cgi?id=1698503\", \"source\": \"af854a3a-2127-422b-91ae-364da2661108\", \"tags\": [\"Permissions Required\", \"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/\", \"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-190\"}]}]"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2021-29946\",\"sourceIdentifier\":\"security@mozilla.org\",\"published\":\"2021-06-24T14:15:09.797\",\"lastModified\":\"2024-11-21T06:02:02.163\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Ports that were written as an integer overflow above the bounds of a 16-bit integer could have bypassed port blocking restrictions when used in the Alt-Svc header. This vulnerability affects Firefox ESR \u003c 78.10, Thunderbird \u003c 78.10, and Firefox \u003c 88.\"},{\"lang\":\"es\",\"value\":\"Los puertos que se escribieron como un desbordamiento de enteros por encima de los l\u00edmites de un entero de 16 bits podr\u00edan haber omitido las restricciones de bloqueo de puertos cuando se usaron en la cabecera Alt-Svc. Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 78.10, Thunderbird versiones anteriores a 78.10 y Firefox versiones anteriores a 88\"}],\"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:U/C:H/I:H/A:H\",\"baseScore\":8.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.8,\"impactScore\":5.9}],\"cvssMetricV2\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"2.0\",\"vectorString\":\"AV:N/AC:M/Au:N/C:P/I:P/A:P\",\"baseScore\":6.8,\"accessVector\":\"NETWORK\",\"accessComplexity\":\"MEDIUM\",\"authentication\":\"NONE\",\"confidentialityImpact\":\"PARTIAL\",\"integrityImpact\":\"PARTIAL\",\"availabilityImpact\":\"PARTIAL\"},\"baseSeverity\":\"MEDIUM\",\"exploitabilityScore\":8.6,\"impactScore\":6.4,\"acInsufInfo\":false,\"obtainAllPrivilege\":false,\"obtainUserPrivilege\":false,\"obtainOtherPrivilege\":false,\"userInteractionRequired\":true}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-190\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"88.0\",\"matchCriteriaId\":\"05F82833-4C58-4D1A-B9FC-EDBE88FF93EA\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"78.10\",\"matchCriteriaId\":\"88984706-ACE5-4873-AC24-9D1670EE94F5\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"78.10\",\"matchCriteriaId\":\"362E8881-7A6C-400C-A128-BBA57710F340\"}]}]}],\"references\":[{\"url\":\"https://bugzilla.mozilla.org/show_bug.cgi?id=1698503\",\"source\":\"security@mozilla.org\",\"tags\":[\"Permissions Required\",\"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\":\"security@mozilla.org\",\"tags\":[\"Release Notes\",\"Vendor Advisory\"]},{\"url\":\"https://bugzilla.mozilla.org/show_bug.cgi?id=1698503\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Permissions Required\",\"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/\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Release Notes\",\"Vendor Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Low",
      "current_release_date": "2025-11-21T16:15:22+00:00",
      "cve": "CVE-2021-29946",
      "id": "CVE-2021-29946",
      "initial_release_date": "2021-04-19T00:00:00+00:00",
      "product_status:fixed": "141",
      "product_status:known_affected": "4",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "Mozilla: Port blocking could be bypassed",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-29946.json",
      "version": "3"
    }
  }
}