CVE-2017-7839

Description

Control characters prepended before "javascript:" URLs pasted in the addressbar can cause the leading characters to be ignored and the pasted JavaScript to be executed instead of being blocked. This could be used in social engineering and self-cross-site-scripting (self-XSS) attacks where users are convinced to copy and paste text into the addressbar. This vulnerability affects Firefox < 57.

Category

6.1
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.73% Top 30%
Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://bugzilla.mozilla.org/show_bug.cgi?id=1402896 issue tracking permissions required
https://www.mozilla.org/security/advisories/mfsa2017-24/ vendor advisory
http://www.securityfocus.com/bid/101832 vdb entry third party advisory
http://www.securitytracker.com/id/1039803 vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2017-7839?
CVE-2017-7839 has been scored as a medium severity vulnerability.
How to fix CVE-2017-7839?
To fix CVE-2017-7839, 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-2017-7839 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2017-7839 is being actively exploited. 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-2017-7839?
CVE-2017-7839 affects Mozilla Firefox.
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