Use-after-return in TigerVNC - CVE-2019-15691
Published: January 3, 2020 / Updated: March 24, 2020
Vulnerability identifier: #VU23905
CSH Severity: High
CVSS v4.0: 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-2019-15691
CWE-ID: CWE-672
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: tigervnc.org
Affected software:
TigerVNC
TigerVNC
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to incorrect usage of stack memory in ZRLEDecoder. If decoding routine would throw an exception, ZRLEDecoder may try to access stack variable, which has been already freed during the process of stack unwinding. A remote attacker can execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
How to mitigate CVE-2019-15691
Install updates from vendor's website.
Sources
- https://github.com/CendioOssman/tigervnc/commit/d61a767d6842b530ffb532ddd5a3d233119aad40
- https://github.com/TigerVNC/tigervnc/releases/tag/v1.10.1
- https://www.openwall.com/lists/oss-security/2019/12/20/2
- https://ics-cert.kaspersky.com/advisories/klcert-advisories/2020/03/23/klcert-20-005-remote-code-execution-on-tigervnc-version-prior-to-1-10-1/