What is CVE-2016-5283?

CVE-2016-5283 is a high-severity vulnerability in Mozilla Firefox, classified under Improper Access Control. CVSS score: 8.8/10. Published 2016-09-22.

How severe is CVE-2016-5283?

High severity. CVSS v3 base score is 8.8 out of 10.

Vulnerability in Mozilla Firefox

CVE-2016-5283

Mozilla Firefox before 49.0 allows remote attackers to bypass the Same Origin Policy via a crafted fragment identifier in the SRC attribute of an IFRAME element, leading to insufficient restrictions on link-color information after a document is resized.

Published 2016-09-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.015 (73.1th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 73.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000

Affected products

Mozilla Firefox

Weakness classification (CWE)

CWE-284 — Improper Access Control

References

www.mozilla.org/security/announce/2016/mfsa2016-85.html (Vendor Advisory)
www.securityfocus.com/bid/93052 (vdb-entry)
security.gentoo.org/glsa/201701-15 (vendor-advisory)
bugzilla.mozilla.org/show_bug.cgi (Issue Tracking)
www.securitytracker.com/id/1036852 (vdb-entry)

Frequently asked questions

What is CVE-2016-5283?: CVE-2016-5283 is a high-severity vulnerability in Mozilla Firefox, classified under Improper Access Control. CVSS score: 8.8/10. Published 2016-09-22.
How severe is CVE-2016-5283?: High severity. CVSS v3 base score is 8.8 out of 10.