Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date: Tue, 12 May 2020 17:46:44 +0530 (IST)
From: P J P <>
To: oss security list <>
cc: Paolo Abeni <>,, 
    Tyler Hicks <>
Subject: CVE-2020-10711 Kernel: NetLabel: null pointer dereference while
 receiving CIPSO packet with null category


NULL pointer dereference(s) issue(s) was found in the Linux kernel's SELinux 
subsystem. It occurs while importing the Commercial IP Security Option (CIPSO) 
protocol's category bitmap into SELinux's extensible bitmap via 
'ebitmap_netlbl_import' routine. While parsing the CIPSO restricted bitmap tag 
in 'cipso_v4_parsetag_rbm' routine, it sets the security attribute to indicate 
that category bitmap is present, even if it has not been allocated. This leads 
to the said NULL pointer dereference issue while importing the same category 
bitmap into SELinux. A remote network user could use this flaw to crash the 
system kernel resulting in DoS scenario.

This issue was introduced by upstream commit:
      netlabel: fix the horribly broken catmap functions

* This issue was reported by Matthew Sheets (CC'd).
* Please see a proposed fix patch attached herein.

Thank you.
Prasad J Pandit / Red Hat Product Security Team
8685 545E B54C 486B C6EB 271E E285 8B5A F050 DE8D
View attachment "linux-netlabel-cope-with-null-catmap.patch" of type "text/plain" (3004 bytes)

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.