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Bug 1427808 (CVE-2017-6410)

Summary: CVE-2017-6410 kf5-kio, kdelibs: Information Leak when accessing https when using a malicious PAC file
Product: [Other] Security Response Reporter: Andrej Nemec <anemec>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED WONTFIX QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: jgrulich, jreznik, kevin, me, rdieter, smparrish, than
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Fixed In Version: kf5-kio 5.32 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2017-03-06 09:21:23 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 1427812, 1427813, 1427814    
Bug Blocks:    

Description Andrej Nemec 2017-03-01 10:03:15 UTC
Using a malicious PAC file, and then using exfiltration methods in the PAC
function FindProxyForURL() enables the attacker to expose full https URLs.

This is a security issue since https URLs may contain sensitive
information in the URL authentication part (user:password@host), and in the
path and the query (e.g. access tokens).

This attack can be carried out remotely (over the LAN) since proxy settings
allow “Detect Proxy Configuration Automatically”.
This setting uses WPAD to retrieve the PAC file, and an attacker who has access
to the victim’s LAN can interfere with the WPAD protocols (DHCP/DNS+HTTP)
and inject his/her own malicious PAC instead of the legitimate one.

External References:

Upstream patches:


Comment 1 Andrej Nemec 2017-03-01 10:07:57 UTC
Created kdelibs tracking bugs for this issue:

Affects: fedora-all [bug 1427813]

Created kf5-kio tracking bugs for this issue:

Affects: epel-7 [bug 1427812]
Affects: fedora-all [bug 1427814]

Comment 3 Fedora Update System 2017-03-12 21:19:54 UTC
kdelibs3-3.5.10-84.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.

Comment 4 Fedora Update System 2017-03-12 21:52:15 UTC
kdelibs3-3.5.10-84.fc25 has been pushed to the Fedora 25 stable repository. If problems still persist, please make note of it in this bug report.