What is CVE-2015-4487?

CVE-2015-4487 is a vulnerability in Mozilla Firefox, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. Published 2015-08-16.

Is CVE-2015-4487 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Mozilla Firefox

CVE-2015-4487

The nsTSubstring::ReplacePrep function in Mozilla Firefox before 40.0, Firefox ESR 38.x before 38.2, and Firefox OS before 2.2 might allow remote attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact via unknown vectors, related to an "overflow."

Vulnerability class: Buffer Overflow

Published 2015-08-16 · last modified 2026-06-17.

CVSS v2 metric

CVSS v2 base score 7.5 (High). Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P. This CVE predates CVSS v3 and has no v3 score from NVD.

EPSS exploit prediction

EPSS: 0.038 (89.7th percentile), scored 2026-09-28.

Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 89.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.038 · newest: 0.038 · change: 0.000

Affected products

Mozilla Firefox — versions 38.0, 38.0.1, 38.0.5
Mozilla Firefox OS
Oracle Solaris — versions 11.3
Canonical Ubuntu Linux — versions 12.04, 14.04, 15.04
openSUSE — versions 13.1, 13.2

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

Public proof-of-concept exploits

References

www.debian.org/security/2015/dsa-3410 (vendor-advisory)
lists.opensuse.org/opensuse-security-announce/2015-11/msg00025.html (vendor-advisory)
www.ubuntu.com/usn/USN-2712-1 (vendor-advisory)
lists.opensuse.org/opensuse-updates/2015-08/msg00031.html (vendor-advisory)
www.ubuntu.com/usn/USN-2702-3 (vendor-advisory)
rhn.redhat.com/errata/RHSA-2015-1682.html (vendor-advisory)
lists.opensuse.org/opensuse-security-announce/2015-08/msg00014.html (vendor-advisory, Third Party Advisory)
lists.opensuse.org/opensuse-updates/2015-08/msg00030.html (vendor-advisory)
rhn.redhat.com/errata/RHSA-2015-1586.html (vendor-advisory)
www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html (Third Party Advisory)

Frequently asked questions

What is CVE-2015-4487?: CVE-2015-4487 is a vulnerability in Mozilla Firefox, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. Published 2015-08-16.
Is CVE-2015-4487 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.