Bug 1277337 (CVE-2015-4515) - CVE-2015-4515 Mozilla: Information disclosure through NTLM authentication (MFSA 2015-117)
Summary: CVE-2015-4515 Mozilla: Information disclosure through NTLM authentication (MF...
Alias: CVE-2015-4515
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On:
Blocks: 1275590
TreeView+ depends on / blocked
Reported: 2015-11-03 05:42 UTC by Huzaifa S. Sidhpurwala
Modified: 2019-09-29 13:39 UTC (History)
1 user (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Last Closed: 2015-11-04 04:57:11 UTC

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Description Huzaifa S. Sidhpurwala 2015-11-03 05:42:05 UTC
Security researcher Tim Brown reported that Firefox discloses the hostname and possibly the Windows domain through NTLM-based HTTP authentication when sending type 3 messages as part of the authentication exchange. This is because the Workstation field is populated with the hostname of the system making the request. An attacker can craft a malicious page to send a silent NTLM request that will disclose the information without visibility in the client, leading to information disclosure. This is mitigated because NTLM v1 is disabled by default configurations. 

External Reference:



Red Hat would like to thank the Mozilla project for reporting this issue. Upstream acknowledges Tim Brown  as the original reporter.


This issue does not affect the version of firefox and thunderbird as shipped with Red Hat Enterprise Linux 5, 6 and 7.

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