CVE-2017-5391

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-06-11 · updated 2026-06-17

Description

Special "about:" pages used by web content, such as RSS feeds, can load privileged "about:" pages in an iframe. If a content-injection bug were found in one of those pages this could allow for potential privilege escalation. This vulnerability affects Firefox < 51.

Affected products

Mozilla Firefox: before 51.0 — fixed in 51.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 51.0. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/95763
http://www.securitytracker.com/id/1037693
https://bugzilla.mozilla.org/show_bug.cgi?id=1309310
https://www.mozilla.org/security/advisories/mfsa2017-01/
http://www.securityfocus.com/bid/95763
http://www.securitytracker.com/id/1037693
https://bugzilla.mozilla.org/show_bug.cgi?id=1309310
https://www.mozilla.org/security/advisories/mfsa2017-01/

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