cbcvebase.
CVE-2018-20019
published 2018-12-19

CVE-2018-20019: LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result…

PriorityP261critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
9.47%
94.9th percentile
LibVNC before commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f contains multiple heap out-of-bound write vulnerabilities in VNC client code that can result remote code execution

Affected

24 ranges
VendorProductVersion rangeFixed in
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
debiandebian_linux
debiandebian_linux
debianlibvncserver< libvncserver 0.9.11+dfsg-1.2 (bookworm)libvncserver 0.9.11+dfsg-1.2 (bookworm)
debianlibvncserver< libvncserver 0.9.11+dfsg-1.3 (bookworm)libvncserver 0.9.11+dfsg-1.3 (bookworm)
debianveyon< libvncserver 0.9.11+dfsg-1.3 (bookworm)libvncserver 0.9.11+dfsg-1.3 (bookworm)
libvnc_projectlibvncserver< 0.9.120.9.12
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.20.9.11+dfsg-1.2
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.30.9.11+dfsg-1.3
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.20.9.11+dfsg-1.2
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.30.9.11+dfsg-1.3
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.20.9.11+dfsg-1.2
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.30.9.11+dfsg-1.3
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.20.9.11+dfsg-1.2
libvncserver_projectlibvncserver>= 0 < 0.9.11+dfsg-1.30.9.11+dfsg-1.3
siemenssimatic_itc1500_firmware>= 3.0.0.0 < 3.2.1.03.2.1.0
siemenssimatic_itc1500_pro_firmware>= 3.0.0.0 < 3.2.1.03.2.1.0
siemenssimatic_itc1900_firmware>= 3.0.0.0 < 3.2.1.03.2.1.0
siemenssimatic_itc1900_pro_firmware>= 3.0.0.0 < 3.2.1.03.2.1.0
siemenssimatic_itc2200_firmware>= 3.0.0.0 < 3.2.1.03.2.1.0
siemenssimatic_itc2200_pro_firmware>= 3.0.0.0 < 3.2.1.03.2.1.0

Detection & IOCsextracted from sources · hover to see the quote

urlhttps://github.com/LibVNC/libvncserver/commit/a83439b9fbe0f03c48eb94ed05729cb016f8b72f
hasha83439b9fbe0f03c48eb94ed05729cb016f8b72f
pathlibvncclient/rfbproto.c
  • The initial upstream patch (commit a83439b9fbe0f03c48eb94ed05729cb016f8b72f) was incomplete; systems patched only to that commit remain vulnerable. Verify fix version is 0.9.12+ or Debian package 0.9.11+dfsg-1.3 or later.
  • Heap out-of-bounds writes occur in libvncclient/rfbproto.c; focus code review and memory-safety tooling (e.g., AddressSanitizer) on that translation unit when analysing suspicious libvncserver builds.
  • ·Red Hat Enterprise Linux 6 is marked 'Will not fix' for CVE-2018-20019; deployments on RHEL 6 running libvncserver will remain permanently unpatched by the vendor.
  • ·The fix for CVE-2018-20019 was incomplete; CVE-2018-20748 tracks the residual heap out-of-bounds write vulnerabilities in libvncclient/rfbproto.c that remained after the initial patch.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
vendor_ubuntu9.8CRITICAL
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