CVE-2018-5134

Description

WebExtensions may use "view-source:" URLs to view local "file:" URL content, as well as content stored in "about:cache", bypassing restrictions that only allow WebExtensions to view specific content. This vulnerability affects Firefox < 59.

Category

7.5
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 1.48% Top 20%
Vendor Advisory ubuntu.com Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
http://www.securityfocus.com/bid/103386 third party advisory vdb entry
https://bugzilla.mozilla.org/show_bug.cgi?id=1429379 permissions required
http://www.securitytracker.com/id/1040514 third party advisory vdb entry
https://usn.ubuntu.com/3596-1/ third party advisory vendor advisory
https://www.mozilla.org/security/advisories/mfsa2018-06/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2018-5134?
CVE-2018-5134 has been scored as a high severity vulnerability.
How to fix CVE-2018-5134?
To fix CVE-2018-5134, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-5134 being actively exploited in the wild?
It is possible that CVE-2018-5134 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2018-5134?
CVE-2018-5134 affects Mozilla Firefox.
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