Bug 1862255 (CVE-2020-14344) - CVE-2020-14344 libX11: Heap overflow in the X input method client
Summary: CVE-2020-14344 libX11: Heap overflow in the X input method client
Alias: CVE-2020-14344
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 1862313 1862314 1862519
Blocks: 1862265
TreeView+ depends on / blocked
Reported: 2020-07-30 20:06 UTC by Pedro Sampaio
Modified: 2021-05-18 15:11 UTC (History)
8 users (show)

Fixed In Version: libX11 1.6.10
Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in libX11. An integer overflow leading to a heap-buffer overflow occurs when setuid programs call XIM client functions while running with elevated privileges. The highest threat from this vulnerability are to data confidentiality and integrity as well as system vulnerability.
Clone Of:
Last Closed: 2021-05-18 14:35:19 UTC

Attachments (Terms of Use)

Description Pedro Sampaio 2020-07-30 20:06:48 UTC
The X Input Method (XIM) client implementation in libX11 has some integer overflows and signed/unsigned comparison issues that can lead to heap corruption when handling malformed messages from an input method.

Comment 1 Adam Jackson 2020-07-30 20:42:35 UTC
This bug is in libX11, not xorg-x11-server.

Comment 3 Huzaifa S. Sidhpurwala 2020-07-31 03:02:45 UTC

Name: X.org project
Upstream: Todd Carson

Comment 5 msiddiqu 2020-07-31 15:34:36 UTC
Public via:


Comment 6 msiddiqu 2020-07-31 15:35:07 UTC
Created libX11 tracking bugs for this issue:

Affects: fedora-all [bug 1862519]

Created xorg-x11-server tracking bugs for this issue:

Affects: fedora-all [bug 1862518]

Comment 7 Huzaifa S. Sidhpurwala 2020-08-01 05:28:41 UTC
External References:


Comment 10 Product Security DevOps Team 2021-05-18 14:35:19 UTC
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):


Comment 11 errata-xmlrpc 2021-05-18 15:11:41 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1804 https://access.redhat.com/errata/RHSA-2021:1804

Note You need to log in before you can comment on or make changes to this bug.