CVE-2018-12386
Status: ModifiedHigh (8.1)—💥 PoC
A vulnerability in register allocation in JavaScript can lead to type confusion, allowing for an arbitrary read and write. This leads to remote code execution inside the sandboxed content process when triggered. This vulnerability affects Firefox ESR < 60.2.2 and Firefox < 62.0.3.
CVSS
- Version: 3.0
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
- Base score: 8.1
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 13%
- Percentile among all scored CVEs: 96
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
💥 Public exploits
Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.
- Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub
⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.
Affected technologies (9)
CWEs
- CWE-704
References
- http://www.securityfocus.com/bid/105460
- http://www.securitytracker.com/id/1041770
- https://access.redhat.com/errata/RHSA-2018:2881
- https://access.redhat.com/errata/RHSA-2018:2884
- https://bugzilla.mozilla.org/show_bug.cgi?id=1493900
- https://security.gentoo.org/glsa/201810-01
- https://usn.ubuntu.com/3778-1/
- https://www.debian.org/security/2018/dsa-4310
- https://www.mozilla.org/security/advisories/mfsa2018-24/
- http://www.securityfocus.com/bid/105460
- http://www.securitytracker.com/id/1041770
- https://access.redhat.com/errata/RHSA-2018:2881
- https://access.redhat.com/errata/RHSA-2018:2884
- https://bugzilla.mozilla.org/show_bug.cgi?id=1493900
- https://security.gentoo.org/glsa/201810-01
- https://usn.ubuntu.com/3778-1/
- https://www.debian.org/security/2018/dsa-4310
- https://www.mozilla.org/security/advisories/mfsa2018-24/
Raw JSON (NVD)
Show
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