CVE-2016-9942

9.8 criticalEPSS 3.8%

Heap-based buffer overflow in ultra.c in LibVNCClient in LibVNCServer before 0.9.11 allows remote servers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted FramebufferUpdate message with the Ultra type tile, such that the LZO payload decompressed length exceeds what is specified by the tile dimensions.

Severity

CVSS 3.0

9.8 critical

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 3.8% chance of exploitation in the next 30 days; higher than 90% of CVEs (scores of 2026-10-31)
CWE: CWE-119
Published: 2016-12-31
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

libvncserver_project:libvncserver

References

http://www.debian.org/security/2017/dsa-3753
http://www.securityfocus.com/bid/95170
https://github.com/LibVNC/libvncserver/pull/137
https://github.com/LibVNC/libvncserver/releases/tag/LibVNCServer-0.9.11
https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html

Check your stack JSON