CVE-2017-5384

Public Exploit

Description

Proxy Auto-Config (PAC) files can specify a JavaScript function called for all URL requests with the full URL path which exposes more information than would be sent to the proxy itself in the case of HTTPS. Normally the Proxy Auto-Config file is specified by the user or machine owner and presumed to be non-malicious, but if a user has enabled Web Proxy Auto Detect (WPAD) this file can be served remotely. This vulnerability affects Firefox < 51.

Category

5.9
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 1.98% Top 20%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.contextis.com//resources/blog/leaking-https-urls-20-year-old-vulnerability/ third party advisory exploit technical description
https://bugzilla.mozilla.org/show_bug.cgi?id=1255474 patch vendor advisory issue tracking
http://www.securitytracker.com/id/1037693 third party advisory vdb entry
https://www.mozilla.org/security/advisories/mfsa2017-01/ vendor advisory
http://www.securityfocus.com/bid/95763 third party advisory vdb entry

Frequently Asked Questions

What is the severity of CVE-2017-5384?
CVE-2017-5384 has been scored as a medium severity vulnerability.
How to fix CVE-2017-5384?
To fix CVE-2017-5384, 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-2017-5384 being actively exploited in the wild?
It is possible that CVE-2017-5384 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2017-5384?
CVE-2017-5384 affects Mozilla Firefox.
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