Bug 1841189 (CVE-2020-13396) - CVE-2020-13396 freerdp: Out-of-bounds read in ntlm_read_ChallengeMessage in winpr/libwinpr/sspi/NTLM/ntlm_message.c.
Summary: CVE-2020-13396 freerdp: Out-of-bounds read in ntlm_read_ChallengeMessage in w...
Alias: CVE-2020-13396
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 1841190 1841191 1841935 1841936
Blocks: 1841202
TreeView+ depends on / blocked
Reported: 2020-05-28 15:40 UTC by Michael Kaplan
Modified: 2020-11-04 02:39 UTC (History)
4 users (show)

Fixed In Version: freerdp 2.1.1
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Last Closed: 2020-09-29 22:01:30 UTC

Attachments (Terms of Use)

System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2020:4031 0 None None None 2020-09-29 20:43:54 UTC
Red Hat Product Errata RHSA-2020:4647 0 None None None 2020-11-04 02:39:00 UTC

Description Michael Kaplan 2020-05-28 15:40:49 UTC
An issue was discovered in FreeRDP before 2.1.1. An out-of-bounds (OOB) read vulnerability has been detected in ntlm_read_ChallengeMessage in winpr/libwinpr/sspi/NTLM/ntlm_message.c.

Upstream Commits:


Comment 1 Michael Kaplan 2020-05-28 15:41:09 UTC
Created freerdp tracking bugs for this issue:

Affects: epel-all [bug 1841190]

Created freerdp1.2 tracking bugs for this issue:

Affects: fedora-all [bug 1841191]

Comment 2 Todd Cullum 2020-05-29 20:36:25 UTC
The patch adds length checking by computing the StartOffset and PayloadOffset with Stream_GetPosition(s) instead of Stream_Pointer(s), then computing the length of the buffer to allocate from those. Also, a NULL check was added prior to copying from stream into buffer. Lastly, The offset and length variables were changed to size_t types. From this info, it looks like that stream pointer could have been pointing to a position which caused an out-of-bounds read of the buffer from within ntlm_read_ChallengeMessage prior to this patch.

Comment 4 errata-xmlrpc 2020-09-29 20:43:52 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2020:4031 https://access.redhat.com/errata/RHSA-2020:4031

Comment 5 Product Security DevOps Team 2020-09-29 22:01:30 UTC
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):


Comment 6 errata-xmlrpc 2020-11-04 02:38:58 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2020:4647 https://access.redhat.com/errata/RHSA-2020:4647

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