CVE-2025-0240

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{"affected": [{"affectedData": [{"product": "Firefox", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "128.*", "status": "unaffected", "version": "128.6", "versionType": "rpm"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "134", "versionType": "rpm"}]}, {"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "128.*", "status": "unaffected", "version": "128.6", "versionType": "rpm"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "134", "versionType": "rpm"}]}], "source": "security@mozilla.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*", "matchCriteriaId": "AEBB7F43-496D-4A67-8E9E-EEE29913B6DE", "versionEndExcluding": "128.6.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*", "matchCriteriaId": "4FDCA935-A68D-404E-A749-CA3845C709F0", "versionEndExcluding": "134.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "matchCriteriaId": "C92D62DE-A681-4B9D-9640-D12D04392A1B", "versionEndExcluding": "128.6.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*", "matchCriteriaId": "A633E231-80F8-4A92-BA69-B9BE5BE45D00", "versionEndExcluding": "134.0", "versionStartIncluding": "129.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Parsing a JavaScript module as JSON could, under some circumstances, cause cross-compartment access, which may result in a use-after-free. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6."}, {"lang": "es", "value": "Analizar un m\u00f3dulo de JavaScript como JSON podr\u00eda, en algunas circunstancias, provocar un acceso entre compartimentos, lo que puede dar lugar a use-after-free. Esta vulnerabilidad afecta a Firefox menor que 134 y Firefox ESR menor que 128.6."}], "id": "CVE-2025-0240", "lastModified": "2026-10-05T15:10:00.590", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "NONE", "baseScore": 4.0, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.5, "impactScore": 1.4, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-0240", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2025-01-08T16:36:55.988099Z", "version": "2.0.3"}}]}, "published": "2025-01-07T16:15:38.663", "references": [{"source": "security@mozilla.org", "tags": ["Issue Tracking", "Permissions Required"], "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1929623"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2025-01/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2025-02/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2025-04/"}, {"source": "security@mozilla.org", "tags": ["Vendor Advisory"], "url": "https://www.mozilla.org/security/advisories/mfsa2025-05/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00004.html"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"affected_release": [{"advisory": "RHSA-2025:0132", "cpe": "cpe:/o:redhat:rhel_els:7", "package": "firefox-0:128.6.0-1.el7_9", "product_name": "Red Hat Enterprise Linux 7 Extended Lifecycle Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0144", "cpe": "cpe:/a:redhat:enterprise_linux:8", "package": "firefox-0:128.6.0-1.el8_10", "product_name": "Red Hat Enterprise Linux 8", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0281", "cpe": "cpe:/a:redhat:enterprise_linux:8", "package": "thunderbird-0:128.6.0-3.el8_10", "product_name": "Red Hat Enterprise Linux 8", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0133", "cpe": "cpe:/a:redhat:rhel_aus:8.2", "package": "firefox-0:128.6.0-1.el8_2", "product_name": "Red Hat Enterprise Linux 8.2 Advanced Update Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0286", "cpe": "cpe:/a:redhat:rhel_aus:8.2", "package": "thunderbird-0:128.6.0-3.el8_2", "product_name": "Red Hat Enterprise Linux 8.2 Advanced Update Support", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0134", "cpe": "cpe:/a:redhat:rhel_aus:8.4", "package": "firefox-0:128.6.0-1.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0287", "cpe": "cpe:/a:redhat:rhel_aus:8.4", "package": "thunderbird-0:128.6.0-3.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0134", "cpe": "cpe:/a:redhat:rhel_tus:8.4", "package": "firefox-0:128.6.0-1.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Telecommunications Update Service", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0287", "cpe": "cpe:/a:redhat:rhel_tus:8.4", "package": "thunderbird-0:128.6.0-3.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Telecommunications Update Service", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0134", "cpe": "cpe:/a:redhat:rhel_e4s:8.4", "package": "firefox-0:128.6.0-1.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0287", "cpe": "cpe:/a:redhat:rhel_e4s:8.4", "package": "thunderbird-0:128.6.0-3.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0136", "cpe": "cpe:/a:redhat:rhel_aus:8.6", "package": "firefox-0:128.6.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0275", "cpe": "cpe:/a:redhat:rhel_aus:8.6", "package": "thunderbird-0:128.6.0-3.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0136", "cpe": "cpe:/a:redhat:rhel_tus:8.6", "package": "firefox-0:128.6.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Telecommunications Update Service", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0275", "cpe": "cpe:/a:redhat:rhel_tus:8.6", "package": "thunderbird-0:128.6.0-3.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Telecommunications Update Service", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0136", "cpe": "cpe:/a:redhat:rhel_e4s:8.6", "package": "firefox-0:128.6.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0275", "cpe": "cpe:/a:redhat:rhel_e4s:8.6", "package": "thunderbird-0:128.6.0-3.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0137", "cpe": "cpe:/a:redhat:rhel_eus:8.8", "package": "firefox-0:128.6.0-1.el8_8", "product_name": "Red Hat Enterprise Linux 8.8 Extended Update Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0284", "cpe": "cpe:/a:redhat:rhel_eus:8.8", "package": "thunderbird-0:128.6.0-3.el8_8", "product_name": "Red Hat Enterprise Linux 8.8 Extended Update Support", "release_date": "2025-01-13T00:00:00Z"}, {"advisory": "RHSA-2025:0080", "cpe": "cpe:/a:redhat:enterprise_linux:9", "package": "firefox-0:128.6.0-1.el9_5", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2025-01-08T00:00:00Z"}, {"advisory": "RHSA-2025:0147", "cpe": "cpe:/a:redhat:enterprise_linux:9", "package": "thunderbird-0:128.6.0-3.el9_5", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0162", "cpe": "cpe:/a:redhat:rhel_e4s:9.0", "package": "firefox-0:128.6.0-1.el9_0", "product_name": "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0165", "cpe": "cpe:/a:redhat:rhel_e4s:9.0", "package": "thunderbird-0:128.6.0-3.el9_0", "product_name": "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0138", "cpe": "cpe:/a:redhat:rhel_eus:9.2", "package": "firefox-0:128.6.0-1.el9_2", "product_name": "Red Hat Enterprise Linux 9.2 Extended Update Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0167", "cpe": "cpe:/a:redhat:rhel_eus:9.2", "package": "thunderbird-0:128.6.0-3.el9_2", "product_name": "Red Hat Enterprise Linux 9.2 Extended Update Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0135", "cpe": "cpe:/a:redhat:rhel_eus:9.4", "package": "firefox-0:128.6.0-1.el9_4", "product_name": "Red Hat Enterprise Linux 9.4 Extended Update Support", "release_date": "2025-01-09T00:00:00Z"}, {"advisory": "RHSA-2025:0166", "cpe": "cpe:/a:redhat:rhel_eus:9.4", "package": "thunderbird-0:128.6.0-3.el9_4", "product_name": "Red Hat Enterprise Linux 9.4 Extended Update Support", "release_date": "2025-01-09T00:00:00Z"}], "bugzilla": {"description": "firefox: Compartment mismatch when parsing JavaScript JSON module", "id": "2336188", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2336188"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H", "status": "verified"}, "cwe": "CWE-416", "details": ["Parsing a JavaScript module as JSON could, under some circumstances, cause cross-compartment access, which may result in a use-after-free. This vulnerability affects Firefox < 134, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6.", "A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue: Parsing a JavaScript module as JSON could, under some circumstances, cause cross-compartment access, which may result in a use-after-free."], "name": "CVE-2025-0240", "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": "firefox-flatpak-container", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "thunderbird-flatpak-container", "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:6", "fix_state": "Out of support scope", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "firefox:flatpak/firefox", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "thunderbird:flatpak/thunderbird", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-01-07T16:07:06Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-0240\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-0240\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=1929623\nhttps://www.mozilla.org/security/advisories/mfsa2025-01/\nhttps://www.mozilla.org/security/advisories/mfsa2025-02/"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Moderate"}

{"analysis": {"en": {"generated_at": "2026-04-20T18:33:29.891031+00:00", "value": {"mitigation_remediation": ["Upgrade Firefox to at least version 134 or Firefox ESR 128.6, and upgrade Thunderbird to at least version 134 or Thunderbird 128.6.\u00a0", "If an upgrade cannot be performed immediately, limit or disable the execution of JavaScript modules from untrusted or external sources in the browser settings or through policy configurations.\u00a0", "Continuously monitor security advisories for any changes to the vulnerability status or additional workarounds and apply subsequent patches as they become available."], "summary": {"action": "Apply Patch", "impact": "Use\u2011after\u2011free leading to possible crash or memory corruption"}, "threat_synthesis": {"affected_systems": "The vulnerability affects Mozilla products, namely Firefox and Thunderbird. The security advisory states that the issue has been fixed in Firefox 134 and Firefox ESR 128.6, as well as in Thunderbird 134 and Thunderbird 128.6. No specific version list is supplied beyond the patched releases.", "description_and_impact": "A JavaScript module that contains JSON can trigger a cross\u2011compartment access flaw, which may cause a use\u2011after\u2011free in the parser. The flaw originates from an improper compartment mismatch handling and is classified as CWE\u2011416. The effect listed in the CVSS score of 4 indicates that the primary consequence is a program crash or unexpected memory corruption, rather than a direct remote code execution.", "risk_and_exploitability": "The EPSS score of less than 1% suggests a very low probability of exploitation, and the vulnerability is not currently listed in CISA\u2019s KEV catalog. The CVSS score of 4 classifies it as low severity. Likely the attack vector requires a crafted JavaScript module delivered to the affected browser, so local or compromised conditions are implied. Because of the low score and limited exploitation probability, the overall risk is considered low, but the use\u2011after\u2011free can still be leveraged to crash the browser or potentially corrupt memory if combined with other weaknesses."}}}}, "created": "2026-04-20T18:45:14.238123+00:00", "updated": "2026-04-20T18:45:14.238133+00:00", "vendors": []}