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 7 Extended Lifecycle Support. The issues 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. These vulnerabilities are fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. The update is rated as Important by Red Hat Product Security.
AI Analysis
Technical Summary
This Red Hat security advisory 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. The advisory applies to Red Hat Enterprise Linux 7 Extended Lifecycle Support versions and provides updated packages to remediate these vulnerabilities.
Potential Impact
Successful exploitation of these vulnerabilities could allow privilege escalation, bypass of process isolation, unsafe access to attributes during XPath parsing, and memory safety issues that may lead to crashes or potential code execution. These issues affect the security and stability of Firefox and Thunderbird on affected Red Hat Enterprise Linux 7 Extended Lifecycle Support systems. The overall impact is rated as high by Red Hat Product Security.
Mitigation Recommendations
Red Hat has released updated Firefox packages for Red Hat Enterprise Linux 7 Extended Lifecycle Support that address these vulnerabilities. Users should apply the security update as detailed in the Red Hat advisory RHSA-2025:4751 and the referenced article https://access.redhat.com/articles/11258. Applying this update remediates the listed vulnerabilities. No additional mitigation steps are indicated by the vendor advisory.
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 7 Extended Lifecycle Support. The issues 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. These vulnerabilities are fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. The update is rated as Important by Red Hat Product Security.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory 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. The advisory applies to Red Hat Enterprise Linux 7 Extended Lifecycle Support versions and provides updated packages to remediate these vulnerabilities.
Potential Impact
Successful exploitation of these vulnerabilities could allow privilege escalation, bypass of process isolation, unsafe access to attributes during XPath parsing, and memory safety issues that may lead to crashes or potential code execution. These issues affect the security and stability of Firefox and Thunderbird on affected Red Hat Enterprise Linux 7 Extended Lifecycle Support systems. The overall impact is rated as high by Red Hat Product Security.
Mitigation Recommendations
Red Hat has released updated Firefox packages for Red Hat Enterprise Linux 7 Extended Lifecycle Support that address these vulnerabilities. Users should apply the security update as detailed in the Red Hat advisory RHSA-2025:4751 and the referenced article https://access.redhat.com/articles/11258. Applying this update remediates the listed vulnerabilities. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:4751
- Cve Count
- 5
- Additional Cves
- ["CVE-2025-4083","CVE-2025-4087","CVE-2025-4091","CVE-2025-4093"]
- Cvss Version
- null
Threat ID: 6a4049ea27e9c79719836468
Added to database: 06/27/2026, 22:08:42 UTC
Last enriched: 06/27/2026, 22:39:51 UTC
Last updated: 06/28/2026, 00:51:09 UTC
Views: 2
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