Bug 1860334 (CVE-2020-14403) - CVE-2020-14403 libvncserver: libvncserver/hextile.c allows out-of-bounds access via encodings
Summary: CVE-2020-14403 libvncserver: libvncserver/hextile.c allows out-of-bounds acce...
Alias: CVE-2020-14403
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 1860335 1860336 1862183 1862184 1862185 1862186
Blocks: 1860332
TreeView+ depends on / blocked
Reported: 2020-07-24 10:24 UTC by Marian Rehak
Modified: 2021-11-02 17:18 UTC (History)
4 users (show)

Fixed In Version: libvncserver 0.9.13
Doc Type: If docs needed, set a value
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Clone Of:
Last Closed: 2021-11-02 17:18:31 UTC

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Description Marian Rehak 2020-07-24 10:24:43 UTC
An issue was discovered in LibVNCServer before 0.9.13. libvncserver/hextile.c allows out-of-bounds access via encodings.

Upstream commit:


Comment 1 Marian Rehak 2020-07-24 10:25:31 UTC
Created libvncserver tracking bugs for this issue:

Affects: epel-7 [bug 1860335]
Affects: fedora-all [bug 1860336]

Comment 2 Todd Cullum 2020-07-30 16:47:31 UTC
in libvncserver/hextile.c's subrectEncode##bpp() rectangle encoder, there's a potential out-of-bounds read due to && operator order. The patch reverses the order. This flaw could potentially cause undefined behavior or a crash if the width (w) is incorrect.

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