Bug 1879981 (CVE-2020-25643) - CVE-2020-25643 kernel: improper input validation in ppp_cp_parse_cr function leads to memory corruption and read overflow
Summary: CVE-2020-25643 kernel: improper input validation in ppp_cp_parse_cr function ...
Keywords:
Status: CLOSED ERRATA
Alias: CVE-2020-25643
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: 1882078 1882079 1882080 1882081 1882082 1883886
Blocks: 1878235
TreeView+ depends on / blocked
 
Reported: 2020-09-17 14:01 UTC by Guilherme de Almeida Suckevicz
Modified: 2023-06-30 10:34 UTC (History)
46 users (show)

Fixed In Version: Linux kernel 5.9-rc7
Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in the HDLC_PPP module of the Linux kernel. Memory corruption and a read overflow is caused by improper input validation in the ppp_cp_parse_cr function which can cause the system to crash or cause a denial of service. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Clone Of:
Environment:
Last Closed: 2020-12-15 22:19:01 UTC
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2021:0138 0 None None None 2021-01-14 11:41:39 UTC
Red Hat Product Errata RHBA-2021:2538 0 None None None 2021-06-23 18:06:01 UTC
Red Hat Product Errata RHBA-2021:2541 0 None None None 2021-06-24 11:51:05 UTC
Red Hat Product Errata RHSA-2020:5437 0 None None None 2020-12-15 11:12:27 UTC
Red Hat Product Errata RHSA-2020:5441 0 None None None 2020-12-15 11:17:26 UTC

Description Guilherme de Almeida Suckevicz 2020-09-17 14:01:23 UTC 
A flaw was found in the Linux Kernel in the HDLC_PPP module. Improper input validation in the ppp_cp_parse_cr function in hdlc_ppp.c leads to memory corruption and read overflow.

Reference and upstream patch:
https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=66d42ed8b25b64eb63111a2b8582c5afc8bf1105
Comment 3 Alex 2020-09-23 18:34:59 UTC 
Mitigation:

To mitigate this issue, prevent modules hdlc_ppp, syncppp from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.
Comment 7 Alex 2020-09-30 13:08:16 UTC 
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 1883886]
Comment 8 Justin M. Forbes 2020-10-01 13:00:04 UTC 
This was fixed for Fedora with the 5.8.12 stable kernel updates.
Comment 9 Petr Matousek 2020-10-01 13:01:45 UTC 
External References:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=66d42ed8b25b64eb63111a2b8582c5afc8bf1105
Comment 11 Alex 2020-10-04 19:25:14 UTC 
Acknowledgments:

Name: ChenNan Of Chaitin (Security Research Lab)
Comment 12 Alex 2020-10-04 19:25:18 UTC 
Statement:

This flaw is rated as a having Moderate impact, because the bug can be triggered only if PPP protocol enabled.
Comment 13 errata-xmlrpc 2020-12-15 11:12:22 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2020:5437 https://access.redhat.com/errata/RHSA-2020:5437
Comment 14 errata-xmlrpc 2020-12-15 11:17:22 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2020:5441 https://access.redhat.com/errata/RHSA-2020:5441
Comment 15 Product Security DevOps Team 2020-12-15 22:19:01 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-2020-25643
Comment 16 errata-xmlrpc 2021-05-18 13:20:19 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1578 https://access.redhat.com/errata/RHSA-2021:1578
Comment 17 errata-xmlrpc 2021-05-18 14:40:41 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1739 https://access.redhat.com/errata/RHSA-2021:1739
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