#VU30157 Out-of-bounds write in LibVNCServer - CVE-2017-18922
Published: June 30, 2020 / Updated: July 17, 2020
Vulnerability identifier: #VU30157
Vulnerability risk: High
CVSSv4.0: 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/E:U/U:Amber
CVE-ID: CVE-2017-18922
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
LibVNCServer
LibVNCServer
Software vendor:
LibVNC
LibVNC
Description
The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
It was discovered that websockets.c in LibVNCServer prior to 0.9.12 did not properly decode certain WebSocket frames. A malicious attacker could exploit this by sending specially crafted WebSocket frames to a server, causing a heap-based buffer overflow.
Remediation
Install update from vendor's website.
External links
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00020.html
- http://www.openwall.com/lists/oss-security/2020/06/30/3
- https://bugzilla.redhat.com/show_bug.cgi?id=1852356
- https://github.com/LibVNC/libvncserver/commit/aac95a9dcf4bbba87b76c72706c3221a842ca433
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NVP7TJVYJDXDFRHVQ3ENEN3H354QPXEZ/
- https://usn.ubuntu.com/4407-1/
- https://www.openwall.com/lists/oss-security/2020/06/30/2