Red Hat Security Advisory: thunderbird security update
Multiple security vulnerabilities affecting Mozilla Thunderbird and Firefox components have been addressed in Red Hat Enterprise Linux 8.2 AppStream. These include spoofing, use-after-free, memory safety bugs, sandbox escapes, information disclosure, mitigation bypass, and clickjacking issues across various components such as Downloads Panel, JavaScript engine, Graphics, IPC, Networking, DOM, and PDF Viewer. The update fixes these issues in Thunderbird ESR 140.7 and Firefox ESR 140.7, as well as Thunderbird 147 and Firefox 147.
AI Analysis
Technical Summary
This Red Hat security advisory addresses a set of 13 vulnerabilities impacting Mozilla Thunderbird and Firefox components packaged in Red Hat Enterprise Linux 8.2 AppStream. The issues include a spoofing vulnerability in the Downloads Panel (CVE-2025-14327), multiple use-after-free bugs in JavaScript and IPC components (CVE-2026-0882, CVE-2026-0884, CVE-2026-0885), memory safety bugs (CVE-2026-0891), sandbox escapes due to incorrect boundary conditions and integer overflow in Graphics and CanvasWebGL components (CVE-2026-0878, CVE-2026-0879, CVE-2026-0880, CVE-2026-0886), information disclosure in Networking and PDF Viewer components (CVE-2026-0883, CVE-2026-0887), mitigation bypass in DOM security (CVE-2026-0877), and spoofing and clickjacking issues in DOM Copy & Paste, Drag & Drop, and PDF Viewer components (CVE-2026-0890). These vulnerabilities were fixed in Thunderbird ESR 140.7 and Firefox ESR 140.7, as well as Thunderbird 147 and Firefox 147. The advisory references Red Hat Bugzilla entries for each CVE and provides updated packages for remediation.
Potential Impact
The vulnerabilities collectively pose risks including spoofing attacks, memory corruption leading to potential crashes or code execution, sandbox escapes that could allow attackers to break out of restricted environments, information disclosure of sensitive data, mitigation bypasses reducing security protections, and clickjacking attacks. These issues affect core components of Thunderbird and Firefox, potentially impacting confidentiality, integrity, and security of the affected systems. The advisory rates the overall impact as Important (high severity). There are no known exploits in the wild at the time of this advisory.
Mitigation Recommendations
Red Hat has released updated Thunderbird packages for Red Hat Enterprise Linux 8.2 AppStream that address these vulnerabilities. Users should apply the security update as described in the Red Hat advisory RHSA-2026:1471 and the referenced article https://access.redhat.com/articles/11258 to remediate these issues. No additional mitigations are specified or required beyond applying the official update.
Red Hat Security Advisory: thunderbird security update
Description
Multiple security vulnerabilities affecting Mozilla Thunderbird and Firefox components have been addressed in Red Hat Enterprise Linux 8.2 AppStream. These include spoofing, use-after-free, memory safety bugs, sandbox escapes, information disclosure, mitigation bypass, and clickjacking issues across various components such as Downloads Panel, JavaScript engine, Graphics, IPC, Networking, DOM, and PDF Viewer. The update fixes these issues in Thunderbird ESR 140.7 and Firefox ESR 140.7, as well as Thunderbird 147 and Firefox 147.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory addresses a set of 13 vulnerabilities impacting Mozilla Thunderbird and Firefox components packaged in Red Hat Enterprise Linux 8.2 AppStream. The issues include a spoofing vulnerability in the Downloads Panel (CVE-2025-14327), multiple use-after-free bugs in JavaScript and IPC components (CVE-2026-0882, CVE-2026-0884, CVE-2026-0885), memory safety bugs (CVE-2026-0891), sandbox escapes due to incorrect boundary conditions and integer overflow in Graphics and CanvasWebGL components (CVE-2026-0878, CVE-2026-0879, CVE-2026-0880, CVE-2026-0886), information disclosure in Networking and PDF Viewer components (CVE-2026-0883, CVE-2026-0887), mitigation bypass in DOM security (CVE-2026-0877), and spoofing and clickjacking issues in DOM Copy & Paste, Drag & Drop, and PDF Viewer components (CVE-2026-0890). These vulnerabilities were fixed in Thunderbird ESR 140.7 and Firefox ESR 140.7, as well as Thunderbird 147 and Firefox 147. The advisory references Red Hat Bugzilla entries for each CVE and provides updated packages for remediation.
Potential Impact
The vulnerabilities collectively pose risks including spoofing attacks, memory corruption leading to potential crashes or code execution, sandbox escapes that could allow attackers to break out of restricted environments, information disclosure of sensitive data, mitigation bypasses reducing security protections, and clickjacking attacks. These issues affect core components of Thunderbird and Firefox, potentially impacting confidentiality, integrity, and security of the affected systems. The advisory rates the overall impact as Important (high severity). There are no known exploits in the wild at the time of this advisory.
Mitigation Recommendations
Red Hat has released updated Thunderbird packages for Red Hat Enterprise Linux 8.2 AppStream that address these vulnerabilities. Users should apply the security update as described in the Red Hat advisory RHSA-2026:1471 and the referenced article https://access.redhat.com/articles/11258 to remediate these issues. No additional mitigations are specified or required beyond applying the official update.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:1471
- Cve Count
- 13
- Additional Cves
- ["CVE-2026-0877","CVE-2026-0878","CVE-2026-0879","CVE-2026-0880","CVE-2026-0882","CVE-2026-0883","CVE-2026-0884","CVE-2026-0885","CVE-2026-0886","CVE-2026-0887","CVE-2026-0890","CVE-2026-0891"]
Threat ID: 6a27e9818dd33fbd851680cf
Added to database: 06/09/2026, 10:22:57 UTC
Last enriched: 07/15/2026, 14:55:10 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 68
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