Heap-based Buffer Overflow Affecting libvncserver0 package, versions <0.9.10-150000.4.41.1


Severity

Recommended
0.0
high
0
10

Based on SUSE Linux Enterprise Server security rating.

Threat Intelligence

EPSS
0.32% (25th percentile)

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  • Snyk IDSNYK-SLES157-LIBVNCSERVER0-19434272
  • published31 Aug 2026
  • disclosed25 Aug 2026

Introduced: 25 Aug 2026

NewCVE-2026-50538  (opens in a new tab)
CWE-122  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade SLES:15.7 libvncserver0 to version 0.9.10-150000.4.41.1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libvncserver0 package and not the libvncserver0 package as distributed by SLES. See How to fix? for SLES:15.7 relevant fixed versions and status.

LibVNCClient is a library for easy implementation of a VNC client. In versions 0.9.12 through 0.9.15, a malicious (or man-in-the-middle) VNC server can force a connecting libvncclient to write attacker-controlled data past the end of its framebuffer. This is an out-of-bounds heap write with attacker-controlled length, contents, and offset. It needs no authentication (the attacker is the server), works in a default build with default settings, and fires from a single FramebufferUpdate the moment the victim connects. It crashes any client unconditionally (denial of service); we also demonstrated it overwriting an application callback pointer and redirecting execution to attacker-chosen code (code execution) under the default configuration. Commit 540332be3e0acc566fa64da6f1b4680c72c724dd patches the issue.

CVSS Base Scores

version 3.1