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{"bugzilla": {"description": "firefox: Information disclosure due to JIT miscompilation in the JavaScript Engine: JIT component", "id": "2442300", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2442300"}, "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"}, "details": ["No description is available for this CVE."], "name": "CVE-2026-2783", "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": "2026-02-24T13:33:16Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-2783\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-2783\nhttps://www.mozilla.org/security/advisories/mfsa2026-15/#CVE-2026-2783"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,148)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox", "source": "cna", "vendor": "Mozilla"}, "product": "firefox", "vendor": "mozilla"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,140.8)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox ESR", "source": "cna", "vendor": "Mozilla"}, "product": "firefox_esr", "vendor": "mozilla"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,148)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Thunderbird", "source": "cna", "vendor": "Mozilla"}, "product": "thunderbird", "vendor": "mozilla"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,140.8)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Thunderbird", "source": "cna", "vendor": "Mozilla"}, "product": "thunderbird", "vendor": "mozilla"}], "analysis": {"en": {"generated_at": "2026-04-15T15:30:03.282751+00:00", "value": {"mitigation_remediation": ["Upgrade to the latest release of Firefox or Thunderbird that includes the fix (Firefox 148 or newer, Firefox ESR 140.8 or newer, Thunderbird 148 or newer, Thunderbird ESR 140.8 or newer).", "If an update cannot be applied immediately, disable JavaScript execution or the JIT engine in the browser or email client settings to reduce the risk of exploitation.", "Continuously monitor Mozilla\u2019s security advisories and update the software as soon as newer patches become available."], "summary": {"action": "Immediate Patch", "impact": "Information Disclosure"}, "threat_synthesis": {"affected_systems": "The issue affects Mozilla Firefox and Thunderbird, including their ESR branches, on all versions released before Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird ESR 140.8. Users on these earlier builds are susceptible to the disclosed flaw.", "description_and_impact": "The vulnerability stems from a miscompilation in the Just\u2011In\u2011Time compiler of the JavaScript engine, which permits a user to read memory content that should not be accessible. This leads to local information disclosure and is classified as CWE-200 and CWE-843, reflecting improper information exposure and the use of data for unintended purposes.", "risk_and_exploitability": "The vulnerability carries a CVSS score of 6.5 and an EPSS score of less than 1 percent, indicating a moderate severity but low probability of exploitation at this time. It does not appear in the CISA KEV catalog. The likely attack vector involves malicious JavaScript executed in a web page or email, enabling a local or remote attacker to trigger the JIT miscompilation. Based on the description, the attack requires the victim to render malicious content, though further details are not explicitly provided."}}}}, "created": "2026-02-25T11:39:26.965737+00:00", "updated": "2026-04-15T17:15:10.561242+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox", "mozilla$PRODUCT$firefox_esr", "mozilla$PRODUCT$thunderbird"]}