LibVNC through 0.9.12 contains a heap out-of-bounds write vulnerability in libvncserver/rfbserver.c. The fix for CVE-2018-15127 was incomplete.
https://www.openwall.com/lists/oss-security/2018/12/10/8
https://github.com/LibVNC/libvncserver/issues/273
https://github.com/LibVNC/libvncserver/commit/09e8fc02f59f16e2583b34fe1a270c238bd9ffec
https://usn.ubuntu.com/3877-1/
https://lists.debian.org/debian-lts-announce/2019/01/msg00029.html
http://www.securityfocus.com/bid/106825
https://lists.debian.org/debian-lts-announce/2019/10/msg00042.html
https://usn.ubuntu.com/4547-1/
https://usn.ubuntu.com/4587-1/
https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf
Source: MITRE
Published: 2019-01-30
Updated: 2022-03-09
Type: CWE-787
Base Score: 7.5
Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 10
Severity: HIGH
Base Score: 9.8
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 3.9
Severity: CRITICAL