Red Hat Security Advisory: firefox security update
Multiple security vulnerabilities affecting Mozilla Firefox and Thunderbird have been addressed in Red Hat Enterprise Linux 8.6 updates. 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 fixes are included in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10 packages provided by Red Hat. The update is rated as Important by Red Hat Product Security.
AI Analysis
Technical Summary
This Red Hat security advisory (RHSA-2025:7544) addresses five vulnerabilities in Mozilla Firefox and Thunderbird. CVE-2025-2817 is a privilege escalation issue in the Firefox Updater. CVE-2025-4087 involves unsafe attribute access during XPath parsing. CVE-2025-4083 is a process isolation bypass using "javascript:" URI links in cross-origin frames. CVE-2025-4091 and CVE-2025-4093 are memory safety bugs fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. Red Hat has released updated packages for Red Hat Enterprise Linux 8.6 variants to remediate these issues. The advisory references detailed CVE pages for further information.
Potential Impact
The vulnerabilities collectively could allow privilege escalation, unsafe data access, bypass of process isolation, and memory safety issues in Firefox and Thunderbird. These could potentially lead to unauthorized actions or crashes. Red Hat rates the security 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 Firefox and Thunderbird packages for Red Hat Enterprise Linux 8.6 variants that address these vulnerabilities. Users should apply these official updates as described in Red Hat article 11258 to remediate the issues. Patch status is confirmed as fixed in Firefox 128.10.0-1.el8_6 and Thunderbird 128.10.0-1.el8_6 packages. No additional mitigation steps are indicated beyond applying the vendor-provided updates.
Red Hat Security Advisory: firefox security update
Description
Multiple security vulnerabilities affecting Mozilla Firefox and Thunderbird have been addressed in Red Hat Enterprise Linux 8.6 updates. 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 fixes are included in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10 packages provided by Red Hat. The update is rated as Important by Red Hat Product Security.
Affected software
pkg:rpm/redhat/firefox-esrRun 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 (RHSA-2025:7544) addresses five vulnerabilities in Mozilla Firefox and Thunderbird. CVE-2025-2817 is a privilege escalation issue in the Firefox Updater. CVE-2025-4087 involves unsafe attribute access during XPath parsing. CVE-2025-4083 is a process isolation bypass using "javascript:" URI links in cross-origin frames. CVE-2025-4091 and CVE-2025-4093 are memory safety bugs fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. Red Hat has released updated packages for Red Hat Enterprise Linux 8.6 variants to remediate these issues. The advisory references detailed CVE pages for further information.
Potential Impact
The vulnerabilities collectively could allow privilege escalation, unsafe data access, bypass of process isolation, and memory safety issues in Firefox and Thunderbird. These could potentially lead to unauthorized actions or crashes. Red Hat rates the security 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 Firefox and Thunderbird packages for Red Hat Enterprise Linux 8.6 variants that address these vulnerabilities. Users should apply these official updates as described in Red Hat article 11258 to remediate the issues. Patch status is confirmed as fixed in Firefox 128.10.0-1.el8_6 and Thunderbird 128.10.0-1.el8_6 packages. No additional mitigation steps are indicated beyond applying the vendor-provided updates.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:7544
- Cve Count
- 5
- Additional Cves
- ["CVE-2025-4083","CVE-2025-4087","CVE-2025-4091","CVE-2025-4093"]
- Cvss Version
- null
Threat ID: 6a4049e827e9c79719835534
Added to database: 06/27/2026, 22:08:40 UTC
Last enriched: 06/27/2026, 22:36:49 UTC
Last updated: 06/27/2026, 23:31:22 UTC
Views: 2
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