Bug 1791207 (CVE-2019-14907) - CVE-2019-14907 samba: Crash after failed character conversion at log level 3 or above
Summary: CVE-2019-14907 samba: Crash after failed character conversion at log level 3 ...
Keywords:
Status: CLOSED ERRATA
Alias: CVE-2019-14907
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1791208 1791209 1791662 1793407
Blocks: 1790872
TreeView+ depends on / blocked
 
Reported: 2020-01-15 08:50 UTC by Huzaifa S. Sidhpurwala
Modified: 2023-12-15 17:11 UTC (History)
19 users (show)

Fixed In Version: samba 4.11.5, samba 4.10.12, samba 4.9.18
Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in samba. When log levels are set at 3 or higher, the string obtained from the client, after a failed character conversion, is printed which could cause long-lived processes to terminate. The highest threat from this vulnerability is to system availability.
Clone Of:
Environment:
Last Closed: 2020-03-23 16:31:58 UTC
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2020:0943 0 None None None 2020-03-23 13:53:59 UTC
Red Hat Product Errata RHSA-2020:1878 0 None None None 2020-04-28 16:03:09 UTC
Red Hat Product Errata RHSA-2020:3981 0 None None None 2020-09-29 20:19:05 UTC

Description Huzaifa S. Sidhpurwala 2020-01-15 08:50:33 UTC 
As per upstream advisory:

If samba is set with "log level = 3" (or above) then the string obtained from the client, after a failed character conversion, is printed.  Such strings can be provided during the NTLMSSP authentication exchange.

In the Samba AD DC in particular, this may cause a long-lived process(such as the RPC server) to terminate.  (In the file server case, the most likely target, smbd, operates as process-per-client and so a crash there is harmless).
Comment 1 Huzaifa S. Sidhpurwala 2020-01-15 08:50:39 UTC 
Acknowledgments:

Name: the Samba project
Upstream: Robert Święcki
Comment 2 Huzaifa S. Sidhpurwala 2020-01-15 08:50:43 UTC 
Mitigation:

Do not set a log level of 3 or above in production.
Comment 5 Huzaifa S. Sidhpurwala 2020-01-21 10:02:08 UTC 
External References:

https://www.samba.org/samba/security/CVE-2019-14907.html
Comment 6 Huzaifa S. Sidhpurwala 2020-01-21 10:03:11 UTC 
Created samba tracking bugs for this issue:

Affects: fedora-all [bug 1793407]
Comment 7 errata-xmlrpc 2020-03-23 13:53:57 UTC 
This issue has been addressed in the following products:

  Red Hat Gluster Storage 3.5 for RHEL 7

Via RHSA-2020:0943 https://access.redhat.com/errata/RHSA-2020:0943
Comment 8 Product Security DevOps Team 2020-03-23 16:31:58 UTC 
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2019-14907
Comment 9 errata-xmlrpc 2020-04-28 16:03:07 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2020:1878 https://access.redhat.com/errata/RHSA-2020:1878
Comment 10 errata-xmlrpc 2020-09-29 20:19:03 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2020:3981 https://access.redhat.com/errata/RHSA-2020:3981
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