CVE-2026-74958 (GCVE-0-2026-74958)

Vulnerability from cvelistv5 – Published: 2026-08-18 12:23 – Updated: 2026-08-18 19:03
VLAI
Title
Information disclosure in the WebRTC component
Summary
Information disclosure in the WebRTC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-18 19:03 UTC
CWE
  • CWE-1021 - Improper Restriction of Rendered UI Layers or Frames
Assigner
References
Impacted products
Vendor Product Version CPE status
Mozilla Firefox Unaffected: 153.1 , ≤ 153.* (rpm)
Unaffected: 154 , ≤ * (rpm)
guessed Create a notification for this product.
Mozilla Thunderbird Unaffected: 153.1 , ≤ 153.* (rpm)
Unaffected: 154 , ≤ * (rpm)
guessed Create a notification for this product.
Credits
Tomoya Nakanishi
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 7.5,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-74958",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-18T19:03:09.604488Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-1021",
                "description": "CWE-1021 Improper Restriction of Rendered UI Layers or Frames",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-18T19:03:15.749Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "153.*",
              "status": "unaffected",
              "version": "153.1",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "154",
              "versionType": "rpm"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "153.*",
              "status": "unaffected",
              "version": "153.1",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "154",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Tomoya Nakanishi"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Information disclosure in the WebRTC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1."
            }
          ],
          "value": "Information disclosure in the WebRTC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-18T18:55:35.088Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2045368"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-74/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-77/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-78/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-80/"
        }
      ],
      "title": "Information disclosure in the WebRTC component"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2026-74958",
    "datePublished": "2026-08-18T12:23:37.936Z",
    "dateReserved": "2026-08-17T11:58:18.135Z",
    "dateUpdated": "2026-08-18T19:03:15.749Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-74958",
      "date": "2026-08-21",
      "epss": "0.00264",
      "percentile": "0.1842"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-74958\",\"sourceIdentifier\":\"security@mozilla.org\",\"published\":\"2026-08-18T13:17:32.910\",\"lastModified\":\"2026-08-19T01:00:14.873\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Information disclosure in the WebRTC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.\"}],\"affected\":[{\"source\":\"security@mozilla.org\",\"affectedData\":[{\"vendor\":\"Mozilla\",\"product\":\"Firefox\",\"versions\":[{\"version\":\"153.1\",\"lessThanOrEqual\":\"153.*\",\"versionType\":\"rpm\",\"status\":\"unaffected\"},{\"version\":\"154\",\"lessThanOrEqual\":\"*\",\"versionType\":\"rpm\",\"status\":\"unaffected\"}]},{\"vendor\":\"Mozilla\",\"product\":\"Thunderbird\",\"versions\":[{\"version\":\"153.1\",\"lessThanOrEqual\":\"153.*\",\"versionType\":\"rpm\",\"status\":\"unaffected\"},{\"version\":\"154\",\"lessThanOrEqual\":\"*\",\"versionType\":\"rpm\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":3.6}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-08-18T19:03:09.604488Z\",\"id\":\"CVE-2026-74958\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"yes\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-1021\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*\",\"versionEndExcluding\":\"153.1.0\",\"matchCriteriaId\":\"21D97347-77F7-440B-9B0D-B97FD4BB38C6\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*\",\"versionEndExcluding\":\"154.0.0\",\"matchCriteriaId\":\"F16EF6DF-DA4B-43C3-A378-66A55A822738\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*\",\"versionEndExcluding\":\"153.1.0\",\"matchCriteriaId\":\"FD0B7622-C417-4F68-A7C0-BD9E897997A1\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*\",\"versionEndExcluding\":\"154.0\",\"matchCriteriaId\":\"D5E5AB38-17E4-4A6E-A147-7B00E988266C\"}]}]}],\"references\":[{\"url\":\"https://bugzilla.mozilla.org/show_bug.cgi?id=2045368\",\"source\":\"security@mozilla.org\",\"tags\":[\"Permissions Required\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-74/\",\"source\":\"security@mozilla.org\",\"tags\":[\"Vendor Advisory\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-77/\",\"source\":\"security@mozilla.org\",\"tags\":[\"Vendor Advisory\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-78/\",\"source\":\"security@mozilla.org\",\"tags\":[\"Vendor Advisory\"]},{\"url\":\"https://www.mozilla.org/security/advisories/mfsa2026-80/\",\"source\":\"security@mozilla.org\",\"tags\":[\"Vendor Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-21T01:06:25+00:00",
      "cve": "CVE-2026-74958",
      "id": "CVE-2026-74958",
      "initial_release_date": "2026-08-18T12:23:37.936000+00:00",
      "product_status:known_not_affected": "23",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "firefox: thunderbird: Information disclosure in the WebRTC component",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74958.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-74958\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-18T19:03:09.604488Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-1021\", \"description\": \"CWE-1021 Improper Restriction of Rendered UI Layers or Frames\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-18T19:02:56.517Z\"}}], \"cna\": {\"title\": \"Information disclosure in the WebRTC component\", \"credits\": [{\"lang\": \"en\", \"value\": \"Tomoya Nakanishi\"}], \"affected\": [{\"vendor\": \"Mozilla\", \"product\": \"Firefox\", \"versions\": [{\"status\": \"unaffected\", \"version\": \"153.1\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"153.*\"}, {\"status\": \"unaffected\", \"version\": \"154\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"*\"}]}, {\"vendor\": \"Mozilla\", \"product\": \"Thunderbird\", \"versions\": [{\"status\": \"unaffected\", \"version\": \"153.1\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"153.*\"}, {\"status\": \"unaffected\", \"version\": \"154\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"*\"}]}], \"references\": [{\"url\": \"https://bugzilla.mozilla.org/show_bug.cgi?id=2045368\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-74/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-77/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-78/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-80/\"}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Information disclosure in the WebRTC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"Information disclosure in the WebRTC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.\", \"base64\": false}]}], \"providerMetadata\": {\"orgId\": \"f16b083a-5664-49f3-a51e-8d479e5ed7fe\", \"shortName\": \"mozilla\", \"dateUpdated\": \"2026-08-18T18:55:35.088Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-74958\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-18T19:03:15.749Z\", \"dateReserved\": \"2026-08-17T11:58:18.135Z\", \"assignerOrgId\": \"f16b083a-5664-49f3-a51e-8d479e5ed7fe\", \"datePublished\": \"2026-08-18T12:23:37.936Z\", \"assignerShortName\": \"mozilla\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.


Detection rules are retrieved from Rulezet.