{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-8974", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-05-19T12:30:22.393Z", "datePublished": "2026-05-19T12:30:23.092Z", "dateUpdated": "2026-05-20T15:39:29.668Z"}, "containers": {"cna": {"affected": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "140.11", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "151", "lessThanOrEqual": "*", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "140.11", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "151", "lessThanOrEqual": "*", "versionType": "rpm"}]}], "descriptions": [{"lang": "en", "value": "Memory safety bugs present in Thunderbird 140.10 and Thunderbird 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Memory safety bugs present in Thunderbird 140.10 and Thunderbird 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11."}]}], "title": "Memory safety bugs fixed in Thunderbird 140.11 and Thunderbird 151", "references": [{"url": "https://bugzilla.mozilla.org/buglist.cgi?bug_id=1784128%2C1883230%2C1983677%2C2022390%2C2023116%2C2023657%2C2024255%2C2024418%2C2024441%2C2024447%2C2024966%2C2025412%2C2025467%2C2025940%2C2025950%2C2025956%2C2026284%2C2027247%2C2027255%2C2027288%2C2027306%2C2027322%2C2027332%2C2027333%2C2028266%2C2028292%2C2028319%2C2028526%2C2028870%2C2028876%2C2028882%2C2029062%2C2029309%2C2029414%2C2029422%2C2029428%2C2029447%2C2029732%2C2029785%2C2029793%2C2029813%2C2029899%2C2031028%2C2031457%2C2032039%2C2033610%2C2033854%2C2034498%2C2034628%2C2034978%2C2035966%2C2036668%2C2036905%2C2036930", "name": "Memory safety bugs fixed in Thunderbird 140.11 and Thunderbird 151"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-46/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-48/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-50/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-51/"}], "credits": [{"lang": "en", "value": "Nika Layzell, Randell Jesup, Timothy Nikkel, Tom Schuster and the Mozilla Fuzzing Team"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-05-19T17:10:52.184Z"}}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-119", "lang": "en", "description": "CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer"}]}], "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-05-20T03:55:33.858670Z", "id": "CVE-2026-8974", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-20T15:39:29.668Z"}}]}}

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{"bugzilla": {"description": "firefox: Memory safety bugs fixed in Firefox ESR 140.11 and Firefox 151", "id": "2479855", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2479855"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "status": "draft"}, "cwe": "CWE-787", "details": ["A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:\nMemory safety bugs present in Firefox ESR 140.10 and Firefox 150. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code."], "name": "CVE-2026-8974", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "rhel10/firefox-flatpak", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-05-19T12:30:23Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-8974\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-8974\nhttps://www.mozilla.org/security/advisories/mfsa2026-48/#CVE-2026-8974"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Moderate"}

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