Integer overflow in Mozilla Firefox
Priority MEDIUM 40CWE-190Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-190 and the CVSS impact.
Summary
A potential vulnerability was found in 32-bit builds where an integer overflow during the conversion of scripts to an internal UTF-16 representation could result in allocating a buffer too small for the conversion. This leads to a possible out-of-bounds write. *Note: 64-bit builds are not vulnerable to this issue.*. This vulnerability affects Firefox < 63, Firefox ESR < 60.3, and Thunderbird < 60.3.
Why it matters now
EPSS 0.03924 90th percentileScored 2026-11-07
Fix Fixed Firefox (Mozilla): 63Firefox ESR (Mozilla): 60.3+1 more productRed Hat: 4 advisories
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Mozilla | Firefox | before 63 | 63 | Patch available | CNA |
| Mozilla | Firefox ESR | before 60.3 | 60.3 | Patch available | CNA |
| Mozilla | Thunderbird | before 60.3 | 60.3 | Patch available | CNA |
- Firefox VendorMozilla Affected before 63 Fixed in 63 Patch available CNA
- Firefox ESR VendorMozilla Affected before 60.3 Fixed in 60.3 Patch available CNA
- Thunderbird VendorMozilla Affected before 60.3 Fixed in 60.3 Patch available CNA
CPE configurations NVD · 18
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:x86:* | before 63.0 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:x86:* | before 60.3 | Vulnerable | Mozilla |
| cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:x86:* | before 60.3 | Vulnerable | Mozilla |
| cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* | 8.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
| cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* | 14.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* | 16.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* | 18.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* | 18.10 | Vulnerable | Canonical |
| cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:* | 6.0 | Vulnerable | Red Hat |
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:x86:* Versions before 63.0 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:x86:* Versions before 60.3 Vulnerable ·Mozilla
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:x86:* Versions before 60.3 Vulnerable ·Mozilla
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
- cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* Versions 14.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* Versions 16.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* Versions 18.10 Vulnerable ·Canonical
- cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
Show 8 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:* | 6.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:* | 7.6 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:* | 7.6 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:* | 7.6 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:* | 6.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:* | 7.0 | Vulnerable | Red Hat |
- cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:* Versions 7.6 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:* Versions 7.6 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:* Versions 7.6 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:* Versions 6.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:* Versions 7.0 Vulnerable ·Red Hat
Remediation
- Fix · CNA Firefox (Mozilla) Fixed in 63
- Fix · CNA Firefox ESR (Mozilla) Fixed in 60.3
- Fix · CNA Thunderbird (Mozilla) Fixed in 60.3
Red Hat 4 advisories
- RHSA-2018:3532 Released 2018-11-09 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux Client (v. 7) thunderbird-60.3.0-1.el7_5
- Red Hat Enterprise Linux Server Optional (v. 7) thunderbird-60.3.0-1.el7_5
- Red Hat Enterprise Linux Workstation (v. 7) thunderbird-60.3.0-1.el7_5
- Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) thunderbird-60.3.0-1.el7_5
- RHSA-2018:3531 Released 2018-11-09 · Red Hat rating Importantthunderbird security update
- Red Hat Enterprise Linux Desktop (v. 6) thunderbird-60.3.0-1.el6
- Red Hat Enterprise Linux Server Optional (v. 6) thunderbird-60.3.0-1.el6
- Red Hat Enterprise Linux Workstation (v. 6) thunderbird-60.3.0-1.el6
- RHSA-2018:3006 Released 2018-10-24 · Red Hat rating Criticalfirefox security update
- Red Hat Enterprise Linux Desktop (v. 6) firefox-60.3.0-1.el6
- Red Hat Enterprise Linux Desktop Optional (v. 6) firefox-60.3.0-1.el6
- Red Hat Enterprise Linux HPC Node Optional (v. 6) firefox-60.3.0-1.el6
- Red Hat Enterprise Linux Server (v. 6) firefox-60.3.0-1.el6
- Red Hat Enterprise Linux Server Optional (v. 6) firefox-60.3.0-1.el6
- Red Hat Enterprise Linux Workstation (v. 6) firefox-60.3.0-1.el6
- Red Hat Enterprise Linux Workstation Optional (v. 6) firefox-60.3.0-1.el6
Show 1 more Red Hat advisories
- RHSA-2018:3005 Released 2018-10-24 · Red Hat rating Criticalfirefox security and bug fix update
- Red Hat Enterprise Linux Client (v. 7) firefox-60.3.0-1.el7_5
- Red Hat Enterprise Linux Client Optional (v. 7) firefox-60.3.0-1.el7_5
- Red Hat Enterprise Linux Server (v. 7) firefox-60.3.0-1.el7_5
- Red Hat Enterprise Linux Server Optional (v. 7) firefox-60.3.0-1.el7_5
- Red Hat Enterprise Linux Workstation (v. 7) firefox-60.3.0-1.el7_5
- Red Hat Enterprise Linux Workstation Optional (v. 7) firefox-60.3.0-1.el7_5
- Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) firefox-60.3.0-1.el7_5
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — USN-3801-1
12 records Highest priority Priority MEDIUM 4 MEDIUM, 8 LOW
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08888 Memory corruption in Mozilla FirefoxPriority MEDIUM 41
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — RHSA-2018:3005
7 records Highest priority Priority MEDIUM 4 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08889 Memory corruption in Mozilla Firefox ESRPriority MEDIUM 43
Show 6 more groups
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — RHSA-2018:3006
7 records Highest priority Priority MEDIUM 4 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08889 Memory corruption in Mozilla Firefox ESRPriority MEDIUM 43
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — GLSA-201811-04
7 records Highest priority Priority MEDIUM 4 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08889 Memory corruption in Mozilla Firefox ESRPriority MEDIUM 43
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — DSA-4324
7 records Highest priority Priority MEDIUM 4 MEDIUM, 3 LOW
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08889 Memory corruption in Mozilla Firefox ESRPriority MEDIUM 43
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — RHSA-2018:3531
4 records Highest priority Priority MEDIUM 4 MEDIUM
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08889 Memory corruption in Mozilla Firefox ESRPriority MEDIUM 43
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — RHSA-2018:3532
4 records Highest priority Priority MEDIUM 4 MEDIUM
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08889 Memory corruption in Mozilla Firefox ESRPriority MEDIUM 43
- Advisory ·
Mozilla Firefox, Firefox ESR, Thunderbird — DSA-4337
4 records Highest priority Priority MEDIUM 4 MEDIUM
Other records, highest priority first
- TI-2018-08892 When manipulating user events in nested loops while opening a document through script, it…Priority MEDIUM 48
- TI-2018-08890 Memory corruption in Mozilla FirefoxPriority MEDIUM 48
- TI-2018-08889 Memory corruption in Mozilla Firefox ESRPriority MEDIUM 43
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux Client (v. 7) | Fixed | RHSA-2018:3005, RHSA-2018:3532 |
| Red Hat Enterprise Linux Client Optional (v. 7) | Fixed | RHSA-2018:3005 |
| Red Hat Enterprise Linux Desktop (v. 6) | Fixed | RHSA-2018:3006, RHSA-2018:3531 |
| Red Hat Enterprise Linux Desktop Optional (v. 6) | Fixed | RHSA-2018:3006 |
| Red Hat Enterprise Linux HPC Node Optional (v. 6) | Fixed | RHSA-2018:3006 |
| Red Hat Enterprise Linux Server (v. 6) | Fixed | RHSA-2018:3006 |
| Red Hat Enterprise Linux Server (v. 7) | Fixed | RHSA-2018:3005 |
| Red Hat Enterprise Linux Server Optional (v. 6) | Fixed | RHSA-2018:3006, RHSA-2018:3531 |
| Red Hat Enterprise Linux Server Optional (v. 7) | Fixed | RHSA-2018:3005, RHSA-2018:3532 |
| Red Hat Enterprise Linux Workstation (v. 6) | Fixed | RHSA-2018:3006, RHSA-2018:3531 |
| Red Hat Enterprise Linux Workstation (v. 7) | Fixed | RHSA-2018:3005, RHSA-2018:3532 |
| Red Hat Enterprise Linux Workstation Optional (v. 6) | Fixed | RHSA-2018:3006 |
| Red Hat Enterprise Linux Workstation Optional (v. 7) | Fixed | RHSA-2018:3005 |
| Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) | Fixed | RHSA-2018:3005 |
| Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) | Fixed | RHSA-2018:3532 |
Not affected: 1 product
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2018-12393
- 2026-10-03 Alias added: GHSA-7372-3rg3-25vw
References
Advisory 16
- DSA-4324
- https://www.mozilla.org/security/advisories/mfsa2018-28/
- https://www.mozilla.org/security/advisories/mfsa2018-26/
- [debian-lts-announce] 20181112 [SECURITY] [DLA 1575-1] thunderbird security update
- GLSA-201811-04
- GLSA-201811-13
- DSA-4337
- https://www.mozilla.org/security/advisories/mfsa2018-27/
- RHSA-2018:3005
- https://bugzilla.mozilla.org/show_bug.cgi?id=1495011
- RHSA-2018:3006
- USN-3801-1
- USN-3868-1
- RHSA-2018:3532
- RHSA-2018:3531
- [debian-lts-announce] 20181107 [SECURITY] [DLA 1571-1] firefox-esr security update
More Mozilla Firefox vulnerabilities
- TI-2024-08981 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.8
- TI-2022-09832 Use after free in Mozilla Firefox KEVCVSS 3.1CRITICAL 9.6
- TI-2019-08769 Improper input validation in Mozilla Firefox ESR KEVCVSS 3.1CRITICAL 10.0
- TI-2010-03577 Mozilla Firefox 3.5.x through 3.5.14 and 3.6.x through 3.6.11, Thunderbird 3.1.6 before… KEVCVSS 3.1CRITICAL 9.8
- TI-2023-04799 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
- TI-2023-04477 Out-of-bounds write in Google Chrome KEVCVSS 3.1HIGH 8.8
Sources
- CVE-2018-12393 · CVE Program
- CVE-2018-12393 · NVD
- FIRST EPSS
- GHSA-7372-3rg3-25vw · GitHub Advisory Database · CC BY 4.0
- CVE-2018-12393 · Red Hat security data · CC BY 4.0
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