Improper input validation in Mozilla Firefox

CVE-2018-12387

A vulnerability where the JavaScript JIT compiler inlines Array.prototype.push with multiple arguments that results in the stack pointer being off by 8 bytes after a bailout. This leaks a memory address to the calling function which can be used as part of an exploit inside the sandboxed content process. This vulnerability affects Firefox ESR < 60.2.2 and Firefox < 62.0.3.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.096 (95.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2018-12387?
CVE-2018-12387 is a critical-severity vulnerability in Mozilla Firefox, classified under Improper Input Validation. CVSS score: 9.1/10. Published 2018-10-18.
How severe is CVE-2018-12387?
Critical severity. CVSS v3 base score is 9.1 out of 10.
Is CVE-2018-12387 known to be exploited?
10 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.