CVE-2025-5263

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{"affected_release": [{"advisory": "RHSA-2025:8341", "cpe": "cpe:/o:redhat:enterprise_linux:10.0", "package": "firefox-0:128.11.0-1.el10_0", "product_name": "Red Hat Enterprise Linux 10", "release_date": "2025-06-02T00:00:00Z"}, {"advisory": "RHSA-2025:8608", "cpe": "cpe:/o:redhat:enterprise_linux:10.0", "package": "thunderbird-0:128.11.0-1.el10_0", "product_name": "Red Hat Enterprise Linux 10", "release_date": "2025-06-05T00:00:00Z"}, {"advisory": "RHSA-2025:9074", "cpe": "cpe:/o:redhat:rhel_els:7", "package": "firefox-0:128.11.0-1.el7_9", "product_name": "Red Hat Enterprise Linux 7 Extended Lifecycle Support", "release_date": "2025-06-16T00:00:00Z"}, {"advisory": "RHSA-2025:8308", "cpe": "cpe:/a:redhat:enterprise_linux:8", "package": "firefox-0:128.11.0-1.el8_10", "product_name": "Red Hat Enterprise Linux 8", "release_date": "2025-05-29T00:00:00Z"}, {"advisory": "RHSA-2025:8756", "cpe": "cpe:/a:redhat:enterprise_linux:8", "package": "thunderbird-0:128.11.0-1.el8_10", "product_name": "Red Hat Enterprise Linux 8", "release_date": "2025-06-10T00:00:00Z"}, {"advisory": "RHSA-2025:8631", "cpe": "cpe:/a:redhat:rhel_aus:8.2", "package": "thunderbird-0:128.11.0-1.el8_2", "product_name": "Red Hat Enterprise Linux 8.2 Advanced Update Support", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:9075", "cpe": "cpe:/a:redhat:rhel_aus:8.2", "package": "firefox-0:128.11.0-1.el8_2", "product_name": "Red Hat Enterprise Linux 8.2 Advanced Update Support", "release_date": "2025-06-16T00:00:00Z"}, {"advisory": "RHSA-2025:8630", "cpe": "cpe:/a:redhat:rhel_aus:8.4", "package": "thunderbird-0:128.11.0-1.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:9076", "cpe": "cpe:/a:redhat:rhel_aus:8.4", "package": "firefox-0:128.11.0-1.el8_4", "product_name": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support", "release_date": "2025-06-16T00:00:00Z"}, {"advisory": "RHSA-2025:8629", "cpe": "cpe:/a:redhat:rhel_aus:8.6", "package": "thunderbird-0:128.11.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:9155", "cpe": "cpe:/a:redhat:rhel_aus:8.6", "package": "firefox-0:128.11.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support", "release_date": "2025-06-17T00:00:00Z"}, {"advisory": "RHSA-2025:8629", "cpe": "cpe:/a:redhat:rhel_tus:8.6", "package": "thunderbird-0:128.11.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Telecommunications Update Service", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:9155", "cpe": "cpe:/a:redhat:rhel_tus:8.6", "package": "firefox-0:128.11.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Telecommunications Update Service", "release_date": "2025-06-17T00:00:00Z"}, {"advisory": "RHSA-2025:8629", "cpe": "cpe:/a:redhat:rhel_e4s:8.6", "package": "thunderbird-0:128.11.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:9155", "cpe": "cpe:/a:redhat:rhel_e4s:8.6", "package": "firefox-0:128.11.0-1.el8_6", "product_name": "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions", "release_date": "2025-06-17T00:00:00Z"}, {"advisory": "RHSA-2025:8628", "cpe": "cpe:/a:redhat:rhel_tus:8.8", "package": "thunderbird-0:128.11.0-1.el8_8", "product_name": "Red Hat Enterprise Linux 8.8 Telecommunications Update Service", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:8628", "cpe": "cpe:/a:redhat:rhel_e4s:8.8", "package": "thunderbird-0:128.11.0-1.el8_8", "product_name": "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:9077", "cpe": "cpe:/a:redhat:rhel_e4s:8.8", "package": "firefox-0:128.11.0-1.el8_8", "product_name": "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions", "release_date": "2025-06-16T00:00:00Z"}, {"advisory": "RHSA-2025:8293", "cpe": "cpe:/a:redhat:enterprise_linux:9", "package": "firefox-0:128.11.0-1.el9_6", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2025-05-29T00:00:00Z"}, {"advisory": "RHSA-2025:8607", "cpe": "cpe:/a:redhat:enterprise_linux:9", "package": "thunderbird-0:128.11.0-1.el9_6", "product_name": "Red Hat Enterprise Linux 9", "release_date": "2025-06-05T00:00:00Z"}, {"advisory": "RHSA-2025:8598", "cpe": "cpe:/a:redhat:rhel_e4s:9.0", "package": "thunderbird-0:128.11.0-1.el9_0", "product_name": "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions", "release_date": "2025-06-05T00:00:00Z"}, {"advisory": "RHSA-2025:9073", "cpe": "cpe:/a:redhat:rhel_e4s:9.0", "package": "firefox-0:128.11.0-1.el9_0", "product_name": "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions", "release_date": "2025-06-16T00:00:00Z"}, {"advisory": "RHSA-2025:8642", "cpe": "cpe:/a:redhat:rhel_e4s:9.2", "package": "thunderbird-0:128.11.0-1.el9_2", "product_name": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions", "release_date": "2025-06-09T00:00:00Z"}, {"advisory": "RHSA-2025:9071", "cpe": "cpe:/a:redhat:rhel_e4s:9.2", "package": "firefox-0:128.11.0-1.el9_2", "product_name": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions", "release_date": "2025-06-16T00:00:00Z"}, {"advisory": "RHSA-2025:8599", "cpe": "cpe:/a:redhat:rhel_eus:9.4", "package": "thunderbird-0:128.11.0-1.el9_4", "product_name": "Red Hat Enterprise Linux 9.4 Extended Update Support", "release_date": "2025-06-05T00:00:00Z"}, {"advisory": "RHSA-2025:9072", "cpe": "cpe:/a:redhat:rhel_eus:9.4", "package": "firefox-0:128.11.0-1.el9_4", "product_name": "Red Hat Enterprise Linux 9.4 Extended Update Support", "release_date": "2025-06-16T00:00:00Z"}], "bugzilla": {"description": "firefox: thunderbird: Error handling for script execution was incorrectly isolated from web content", "id": "2368756", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2368756"}, "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": "verified"}, "cwe": "CWE-829", "details": ["Error handling for script execution was incorrectly isolated from web content, which could have allowed cross-origin leak attacks. This vulnerability affects Firefox < 139, Firefox ESR < 115.24, Firefox ESR < 128.11, Thunderbird < 139, and Thunderbird < 128.11.", "A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue: Error handling for script execution is incorrectly isolated from web content, which could allow cross-origin leak attacks."], "name": "CVE-2025-5263", "package_state": [{"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:10", "fix_state": "Affected", "package_name": "rhel10/thunderbird-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: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"}], "public_date": "2025-05-27T12:29:22Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-5263\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-5263\nhttps://www.mozilla.org/en-US/security/advisories/mfsa2025-44/#CVE-2025-5263\nhttps://www.mozilla.org/en-US/security/advisories/mfsa2025-46/#CVE-2025-5263"], "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": "2026-04-20T20:30:52.404416+00:00", "value": {"mitigation_remediation": ["Apply the latest Mozilla Firefox patch (139 or newer) or the corresponding ESR release (115.24 or 128.11), and update Thunderbird to\u202f139 or newer or ESR\u202f128.11.", "Remove or disable any browser or add\u2011on extensions that alter script execution or error handling, as these can enable the CWE\u2011346 leakage path.", "If an immediate update is impossible, configure the browser\u2019s security settings or group policy to block cross\u2011origin script execution and to enforce strict same\u2011origin constraints, mitigating the risk of CWE\u2011829."], "summary": {"action": "Patch", "impact": "Information Disclosure via Cross\u2011origin Leak"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox and Mozilla Thunderbird are impacted. Versions before Firefox\u202f139, Firefox\u202fESR\u202f115.24, Firefox\u202fESR\u202f128.11 and before Thunderbird\u202f139, Thunderbird\u202fESR\u202f128.11 are vulnerable. Packages from Red\u202fHat Enterprise\u202fLinux\u202f8,\u202f9, and associated RHEL derivatives that include these browsers also require attention.", "description_and_impact": "This vulnerability arises when the routines that handle execution errors are incorrectly isolated from web content. A crafted page can trigger those routines and expose data that belongs to another origin. The flaw can leak sensitive information but does not permit arbitrary code execution or modification of system state. The weakness is aligned with CWE\u2011346 (Untrusted Content as Source) and CWE\u2011829 (Improper Restriction of Execution Graph).", "risk_and_exploitability": "With a CVSS score of\u202f4.3 the issue is low severity, and an EPSS of\u00a0<\u00a01\u00a0% signals a very small chance of exploitation. It is not present in the CISA KEV catalog. The attack vector is not documented in the advisory; however, the description suggests that a malicious or compromised web page would be needed to provoke the vulnerable error\u2011handling path. Because no privilege escalation is required, the risk is mainly limited to unintended information disclosure."}}}}, "created": "2026-04-20T20:45:16.928799+00:00", "updated": "2026-04-20T20:45:16.928809+00:00", "vendors": []}