CVE-2016-5291

Severity: medium (CVSS 5.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-06-11 · updated 2026-06-17
Weakness: CWE-20

Description

A same-origin policy bypass with local shortcut files to load arbitrary local content from disk. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.

Affected products

Debian Linux: 8.0
Mozilla Firefox: before 45.5.0; before 50.0 — fixed in 45.5.0, 50.0
Mozilla Thunderbird: before 45.5.0 — fixed in 45.5.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 45.5.0, 50.0; Mozilla Thunderbird 45.5.0. Check the vendor advisory for mitigations.

References

http://rhn.redhat.com/errata/RHSA-2016-2780.html
http://www.securityfocus.com/bid/94336
http://www.securitytracker.com/id/1037298
https://bugzilla.mozilla.org/show_bug.cgi?id=1292159
https://security.gentoo.org/glsa/201701-15
https://www.debian.org/security/2016/dsa-3730
https://www.mozilla.org/security/advisories/mfsa2016-89/
https://www.mozilla.org/security/advisories/mfsa2016-90/
https://www.mozilla.org/security/advisories/mfsa2016-93/
http://rhn.redhat.com/errata/RHSA-2016-2780.html
http://www.securityfocus.com/bid/94336
http://www.securitytracker.com/id/1037298

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