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."

Published: 2015-08-16 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2015-4487 is rated Moderate Risk (59.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.26%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2015-4487

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-13 2.68% 2.26% -0.41%
2 2025-12-28 2.26% 2.68% +0.41%
3 2025-12-27 — 2.26% —

Full EPSS history (18 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2015-4487

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2015-4487

OS Trackers for CVE-2015-4487

vendor priority summary link
gentoo normal CVE-2015-4487: 1 GLSA(s) (201605-06), 6 atom(s) (dev-libs/nspr, dev-libs/nss, mail-client/thunderbird, mail-client/thunderbird-bin, www-client/firefox, www-client/firefox-bin); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2015-4487
redhat medium — https://access.redhat.com/security/cve/CVE-2015-4487
suse high CVE-2015-4487 severity important: SUSE including 156 source package names (MozillaFirefox-102.11.0-150200.152.87.1, MozillaFirefox-115.10.0-150200.152.134.1, …), 350 product×package rows across 74 product lines (Image SLES12-SP5-Azure-BYOS, Image SLES12-SP5-Azure-Basic-On-Demand, … (74 product lines)): Fixed 335, Known Not Affected 15. https://www.suse.com/security/cve/CVE-2015-4487/
ubuntu medium CVE-2015-4487 medium priority: Ubuntu including 2 source packages (firefox, thunderbird), 8 status rows across 4 suites (precise, trusty, upstream, vivid): released 8. https://ubuntu.com/security/CVE-2015-4487

Affected software / configurations for CVE-2015-4487

Vendor Product Version Raw CPE
mozilla firefox <= 39.0.3 cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
mozilla firefox 38.0 cpe:2.3:a:mozilla:firefox:38.0:*:*:*:*:*:*:*
mozilla firefox 38.0.1 cpe:2.3:a:mozilla:firefox:38.0.1:*:*:*:*:*:*:*
mozilla firefox 38.0.5 cpe:2.3:a:mozilla:firefox:38.0.5:*:*:*:*:*:*:*
mozilla firefox 38.1.0 cpe:2.3:a:mozilla:firefox:38.1.0:*:*:*:*:*:*:*
mozilla firefox_os <= 2.1.0 cpe:2.3:o:mozilla:firefox_os:*:*:*:*:*:*:*:*
canonical ubuntu_linux 12.04 cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 14.04 cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 15.04 cpe:2.3:o:canonical:ubuntu_linux:15.04:*:*:*:*:*:*:*
opensuse opensuse 13.1 cpe:2.3:o:opensuse:opensuse:13.1:*:*:*:*:*:*:*
opensuse opensuse 13.2 cpe:2.3:o:opensuse:opensuse:13.2:*:*:*:*:*:*:*
oracle solaris 11.3 cpe:2.3:o:oracle:solaris:11.3:*:*:*:*:*:*:*

References for CVE-2015-4487

URL Tags
http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00014.html Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00015.html Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00021.html
http://lists.opensuse.org/opensuse-security-announce/2015-09/msg00016.html
http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00025.html
http://lists.opensuse.org/opensuse-updates/2015-08/msg00030.html
http://lists.opensuse.org/opensuse-updates/2015-08/msg00031.html
http://rhn.redhat.com/errata/RHSA-2015-1586.html
http://rhn.redhat.com/errata/RHSA-2015-1682.html
http://www.debian.org/security/2015/dsa-3333
http://www.debian.org/security/2015/dsa-3410
http://www.mozilla.org/security/announce/2015/mfsa2015-90.html Vendor Advisory
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html Third Party Advisory
http://www.securitytracker.com/id/1033247
http://www.securitytracker.com/id/1033372
http://www.ubuntu.com/usn/USN-2702-1 Third Party Advisory
http://www.ubuntu.com/usn/USN-2702-2 Third Party Advisory
http://www.ubuntu.com/usn/USN-2702-3
http://www.ubuntu.com/usn/USN-2712-1
https://bugzilla.mozilla.org/show_bug.cgi?id=1171603 Issue Tracking
https://security.gentoo.org/glsa/201605-06
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