CVE-2015-4487
CVE-2015-4487 is a high-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.
Key facts
- Severity: High (CVSS 2.0 base score 7.5)
- EPSS exploit prediction: 4% (89th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Mozilla Firefox
- Published:
- Last modified:
Description
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."
Frequently asked questions
- What is 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."
- How severe is CVE-2015-4487?
- CVE-2015-4487 has a CVSS 2.0 base score of 7.5, rated high severity.
- Is CVE-2015-4487 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2015-4487?
- CVE-2015-4487 primarily affects Mozilla Firefox. In total, 12 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2015-4487?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2015-4487 published?
- CVE-2015-4487 was published on 2015-08-16 and last updated on 2026-06-17.
References
- http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00014.html
- http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00015.html
- 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
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
- http://www.securitytracker.com/id/1033247
- http://www.securitytracker.com/id/1033372
- http://www.ubuntu.com/usn/USN-2702-1
- http://www.ubuntu.com/usn/USN-2702-2
- 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
- https://security.gentoo.org/glsa/201605-06
Affected products (12)
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:firefox:38.0:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:firefox:38.0.1:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:firefox:38.0.5:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:firefox:38.1.0:*:*:*:*:*:*:*
- cpe:2.3:o:mozilla:firefox_os:*:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:15.04:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:opensuse:13.1:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:opensuse:13.2:*:*:*:*:*:*:*
- cpe:2.3:o:oracle:solaris:11.3:*:*:*:*:*:*:*
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