CVE-2018-12379
CVE-2018-12379 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 4.6
- EPSS exploit prediction: 0% (31st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Mozilla Firefox
- Published:
- Last modified:
Description
When the Mozilla Updater opens a MAR format file which contains a very long item filename, an out-of-bounds write can be triggered, leading to a potentially exploitable crash. This requires running the Mozilla Updater manually on the local system with the malicious MAR file in order to occur. This vulnerability affects Firefox < 62, Firefox ESR < 60.2, and Thunderbird < 60.2.1.
Frequently asked questions
- What is CVE-2018-12379?
- When the Mozilla Updater opens a MAR format file which contains a very long item filename, an out-of-bounds write can be triggered, leading to a potentially exploitable crash. This requires running the Mozilla Updater manually on the local system with the malicious MAR file in order to occur. This vulnerability affects Firefox < 62, Firefox ESR < 60.2, and Thunderbird < 60.2.1.
- How severe is CVE-2018-12379?
- CVE-2018-12379 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2018-12379 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2018-12379?
- CVE-2018-12379 primarily affects Mozilla Firefox. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2018-12379?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2018-12379 published?
- CVE-2018-12379 was published on 2018-10-18 and last updated on 2026-06-17.
References
- http://www.securityfocus.com/bid/105280
- http://www.securitytracker.com/id/1041610
- https://access.redhat.com/errata/RHSA-2018:2692
- https://access.redhat.com/errata/RHSA-2018:2693
- https://access.redhat.com/errata/RHSA-2018:3403
- https://access.redhat.com/errata/RHSA-2018:3458
- https://bugzilla.mozilla.org/show_bug.cgi?id=1473113
- https://lists.debian.org/debian-lts-announce/2018/11/msg00011.html
- https://security.gentoo.org/glsa/201810-01
- https://security.gentoo.org/glsa/201811-13
- https://www.debian.org/security/2018/dsa-4327
- https://www.mozilla.org/security/advisories/mfsa2018-20/
- https://www.mozilla.org/security/advisories/mfsa2018-21/
- https://www.mozilla.org/security/advisories/mfsa2018-25/
Affected products (14)
- cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_eus:7.5:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
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