Red Hat Security Advisory: firefox security update
Two security vulnerabilities (CVE-2025-4918 and CVE-2025-4919) affecting Mozilla Firefox and Thunderbird were addressed by Red Hat in an important security update for Red Hat Enterprise Linux 8.6. Both issues involve out-of-bounds access errors related to Promise object resolution and linear sum optimization. Red Hat has released updated Firefox packages to remediate these vulnerabilities.
AI Analysis
Technical Summary
Red Hat Product Security issued an advisory (RHSA-2025:8645) for Mozilla Firefox and Thunderbird addressing two out-of-bounds access vulnerabilities: CVE-2025-4918 occurs when resolving Promise objects, and CVE-2025-4919 occurs during optimization of linear sums. These vulnerabilities are categorized under CWE-787 (Out-of-bounds Write). The advisory updates Firefox packages for Red Hat Enterprise Linux 8.6 variants, providing fixes to prevent potential memory safety issues. No CVSS scores are provided in the advisory, but the update is rated as Important by Red Hat.
Potential Impact
The vulnerabilities allow out-of-bounds memory access which could lead to memory corruption or crashes. The exact impact details and exploitability are not specified in the advisory. No known exploits in the wild have been reported. The issues affect Firefox and Thunderbird components as packaged by Red Hat for RHEL 8.6.
Mitigation Recommendations
Red Hat has released updated Firefox packages for Red Hat Enterprise Linux 8.6 to address these vulnerabilities. Users should apply the official security update as described in Red Hat advisory RHSA-2025:8645. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor.
Red Hat Security Advisory: firefox security update
Description
Two security vulnerabilities (CVE-2025-4918 and CVE-2025-4919) affecting Mozilla Firefox and Thunderbird were addressed by Red Hat in an important security update for Red Hat Enterprise Linux 8.6. Both issues involve out-of-bounds access errors related to Promise object resolution and linear sum optimization. Red Hat has released updated Firefox packages to remediate these vulnerabilities.
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Red Hat Product Security issued an advisory (RHSA-2025:8645) for Mozilla Firefox and Thunderbird addressing two out-of-bounds access vulnerabilities: CVE-2025-4918 occurs when resolving Promise objects, and CVE-2025-4919 occurs during optimization of linear sums. These vulnerabilities are categorized under CWE-787 (Out-of-bounds Write). The advisory updates Firefox packages for Red Hat Enterprise Linux 8.6 variants, providing fixes to prevent potential memory safety issues. No CVSS scores are provided in the advisory, but the update is rated as Important by Red Hat.
Potential Impact
The vulnerabilities allow out-of-bounds memory access which could lead to memory corruption or crashes. The exact impact details and exploitability are not specified in the advisory. No known exploits in the wild have been reported. The issues affect Firefox and Thunderbird components as packaged by Red Hat for RHEL 8.6.
Mitigation Recommendations
Red Hat has released updated Firefox packages for Red Hat Enterprise Linux 8.6 to address these vulnerabilities. Users should apply the official security update as described in Red Hat advisory RHSA-2025:8645. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:8645
- Cve Count
- 2
- Additional Cves
- ["CVE-2025-4919"]
Threat ID: 6a4049e227e9c79719833099
Added to database: 06/27/2026, 22:08:34 UTC
Last enriched: 06/27/2026, 22:29:45 UTC
Last updated: 09/10/2026, 19:36:50 UTC
Views: 20
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