Red Hat Security Advisory: firefox security update
Multiple security vulnerabilities affecting Mozilla Firefox and Thunderbird have been addressed in a Red Hat security update for Red Hat Enterprise Linux 8.2. These include privilege escalation in the Firefox Updater, unsafe attribute access during XPath parsing, process isolation bypass via "javascript:" URI links in cross-origin frames, and several memory safety bugs. The update fixes these issues in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. Red Hat has rated the security impact as Important and recommends applying the update to affected systems.
AI Analysis
Technical Summary
This Red Hat security advisory addresses five vulnerabilities in Mozilla Firefox and Thunderbird. The issues include CVE-2025-2817 (privilege escalation in Firefox Updater), CVE-2025-4087 (unsafe attribute access during XPath parsing), CVE-2025-4083 (process isolation bypass using "javascript:" URI links in cross-origin frames), and two memory safety bugs (CVE-2025-4091 and CVE-2025-4093) fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. The advisory provides updated packages for Red Hat Enterprise Linux 8.2 to remediate these vulnerabilities. No CVSS scores are provided in the advisory, but the overall impact is rated as Important by Red Hat Product Security.
Potential Impact
The vulnerabilities include privilege escalation, unsafe attribute access, process isolation bypass, and memory safety bugs. These issues could potentially allow an attacker to escalate privileges, bypass security boundaries between processes, or cause memory corruption leading to crashes or code execution. The advisory does not report known exploits in the wild. The impact is rated Important, indicating a significant security risk if unpatched.
Mitigation Recommendations
Red Hat has released updated Firefox and Thunderbird packages for Red Hat Enterprise Linux 8.2 that address these vulnerabilities. Users should apply the security update as described in the Red Hat advisory (RHSA-2025:7547) and the referenced article https://access.redhat.com/articles/11258. No additional mitigations are specified or required beyond applying the official update.
Red Hat Security Advisory: firefox security update
Description
Multiple security vulnerabilities affecting Mozilla Firefox and Thunderbird have been addressed in a Red Hat security update for Red Hat Enterprise Linux 8.2. These include privilege escalation in the Firefox Updater, unsafe attribute access during XPath parsing, process isolation bypass via "javascript:" URI links in cross-origin frames, and several memory safety bugs. The update fixes these issues in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. Red Hat has rated the security impact as Important and recommends applying the update to affected systems.
Affected software
pkg:rpm/redhat/firefoxpkg:rpm/redhat/thunderbirdRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory addresses five vulnerabilities in Mozilla Firefox and Thunderbird. The issues include CVE-2025-2817 (privilege escalation in Firefox Updater), CVE-2025-4087 (unsafe attribute access during XPath parsing), CVE-2025-4083 (process isolation bypass using "javascript:" URI links in cross-origin frames), and two memory safety bugs (CVE-2025-4091 and CVE-2025-4093) fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. The advisory provides updated packages for Red Hat Enterprise Linux 8.2 to remediate these vulnerabilities. No CVSS scores are provided in the advisory, but the overall impact is rated as Important by Red Hat Product Security.
Potential Impact
The vulnerabilities include privilege escalation, unsafe attribute access, process isolation bypass, and memory safety bugs. These issues could potentially allow an attacker to escalate privileges, bypass security boundaries between processes, or cause memory corruption leading to crashes or code execution. The advisory does not report known exploits in the wild. The impact is rated Important, indicating a significant security risk if unpatched.
Mitigation Recommendations
Red Hat has released updated Firefox and Thunderbird packages for Red Hat Enterprise Linux 8.2 that address these vulnerabilities. Users should apply the security update as described in the Red Hat advisory (RHSA-2025:7547) and the referenced article https://access.redhat.com/articles/11258. 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-2025:7547
- Cve Count
- 5
- Additional Cves
- ["CVE-2025-4083","CVE-2025-4087","CVE-2025-4091","CVE-2025-4093"]
Threat ID: 6a4049e827e9c7971983526a
Added to database: 06/27/2026, 22:08:40 UTC
Last enriched: 06/27/2026, 22:36:38 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 28
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