Heap out-of-bounds write in LibVNCServer - CVE-2018-20750
Published: February 18, 2019 / Updated: November 25, 2019
Vulnerability identifier: #VU17750
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2018-20750
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error. A remote attacker can trigger out-of-bounds write in rfbserver.c and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
LibVNCServer
Ubuntu
Opensuse
libvncserver0 (Ubuntu package)
libvncclient1 (Ubuntu package)
libvncserver1 (Ubuntu package)
italc-master (Ubuntu package)
libitalccore (Ubuntu package)
italc-client (Ubuntu package)
SIMATIC ITC2200 PRO
SIMATIC ITC2200
SIMATIC ITC1900 PRO
SIMATIC ITC1900
SIMATIC ITC1500 PRO
SIMATIC ITC1500
Ubuntu
Opensuse
libvncserver0 (Ubuntu package)
libvncclient1 (Ubuntu package)
libvncserver1 (Ubuntu package)
italc-master (Ubuntu package)
libitalccore (Ubuntu package)
italc-client (Ubuntu package)
SIMATIC ITC2200 PRO
SIMATIC ITC2200
SIMATIC ITC1900 PRO
SIMATIC ITC1900
SIMATIC ITC1500 PRO
SIMATIC ITC1500
How to mitigate CVE-2018-20750
Update to version 0.9.12.
LibVNCServer - update to 0.9.12
libvncserver0 (Ubuntu package) - update to 0.9.9+dfsg-1ubuntu1.4
libvncclient1 (Ubuntu package) - addressed in versions 0.9.10+dfsg-3ubuntu0.16.04.3, 0.9.11+dfsg-1ubuntu1.1, 0.9.11+dfsg-1.1ubuntu0.1
libvncserver1 (Ubuntu package) - addressed in versions 0.9.10+dfsg-3ubuntu0.16.04.3, 0.9.11+dfsg-1ubuntu1.1, 0.9.11+dfsg-1.1ubuntu0.1
SIMATIC ITC2200 PRO - update to
SIMATIC ITC2200 PRO - update to 3.2.1.0
SIMATIC ITC2200 - update to 3.2.1.0
SIMATIC ITC1900 PRO - update to 3.2.1.0
SIMATIC ITC1900 - update to 3.2.1.0
SIMATIC ITC1500 PRO - update to 3.2.1.0
SIMATIC ITC1500 - update to 3.2.1.0
italc-master (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
libitalccore (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
italc-client (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
libvncserver0 (Ubuntu package) - update to 0.9.9+dfsg-1ubuntu1.4
libvncclient1 (Ubuntu package) - addressed in versions 0.9.10+dfsg-3ubuntu0.16.04.3, 0.9.11+dfsg-1ubuntu1.1, 0.9.11+dfsg-1.1ubuntu0.1
libvncserver1 (Ubuntu package) - addressed in versions 0.9.10+dfsg-3ubuntu0.16.04.3, 0.9.11+dfsg-1ubuntu1.1, 0.9.11+dfsg-1.1ubuntu0.1
SIMATIC ITC2200 PRO - update to
SIMATIC ITC2200 PRO - update to 3.2.1.0
SIMATIC ITC2200 - update to 3.2.1.0
SIMATIC ITC1900 PRO - update to 3.2.1.0
SIMATIC ITC1900 - update to 3.2.1.0
SIMATIC ITC1500 PRO - update to 3.2.1.0
SIMATIC ITC1500 - update to 3.2.1.0
italc-master (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
libitalccore (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
italc-client (Ubuntu package) - update to 1:3.0.3+dfsg1-3ubuntu0.1
External References
- https://github.com/LibVNC/libvncserver/commit/a64c3b37af9a6c8f8009d7516874b8d266b42bae
- https://github.com/LibVNC/libvncserver/commit/c2c4b81e6cb3b485fb1ec7ba9e7defeb889f6ba7
- https://github.com/LibVNC/libvncserver/commit/c5ba3fee85a7ecbbca1df5ffd46d32b92757bc2a
- https://github.com/LibVNC/libvncserver/commit/e34bcbb759ca5bef85809967a268fdf214c1ad2c
- https://github.com/LibVNC/libvncserver/issues/273
- https://www.openwall.com/lists/oss-security/2018/12/10/8