What is CVE-2016-5290?

CVE-2016-5290 is a critical-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2018-06-11.

How severe is CVE-2016-5290?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2016-5290 known to be exploited?

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

Buffer overflow in Mozilla Firefox

CVE-2016-5290

Memory safety bugs were reported in Firefox 49 and Firefox ESR 45.4. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.

Vulnerability class: Buffer Overflow

Published 2018-06-11 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.032 (87.6th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 88th percentile — 87.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.032 · newest: 0.032 · change: 0.000

Affected products

Mozilla Firefox — versions unspecified
Mozilla Firefox Esr — versions unspecified
Mozilla Thunderbird — versions unspecified
Debian Linux — versions 8.0

Weakness classification (CWE)

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

Public proof-of-concept exploits

ARPSyndicate/cvemon

References

www.debian.org/security/2016/dsa-3730 (vendor-advisory, Third Party Advisory)
rhn.redhat.com/errata/RHSA-2016-2825.html (vendor-advisory, Third Party Advisory)
bugzilla.mozilla.org/buglist.cgi (Vendor Advisory)
www.securityfocus.com/bid/94335 (VDB Entry, Third Party Advisory, vdb-entry)
www.securitytracker.com/id/1037298 (VDB Entry, Third Party Advisory, vdb-entry)
security.gentoo.org/glsa/201701-15 (vendor-advisory, Third Party Advisory)
www.mozilla.org/security/advisories/mfsa2016-93/ (Vendor Advisory)
rhn.redhat.com/errata/RHSA-2016-2780.html (vendor-advisory, Third Party Advisory)
www.mozilla.org/security/advisories/mfsa2016-89/ (Vendor Advisory)
www.mozilla.org/security/advisories/mfsa2016-90/ (Vendor Advisory)

Frequently asked questions

What is CVE-2016-5290?: CVE-2016-5290 is a critical-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2018-06-11.
How severe is CVE-2016-5290?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2016-5290 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.