High severity · published Mar 10, 2022
CVE-2022-24750
Low privilege user is able to exploit the service and gain SYSTEM privileges in UltraVNC server
7.8
CVSS
0.3%
EPSS
No
On KEV
Description
UltraVNC is a free and open source remote pc access software. A vulnerability has been found in versions prior to 1.3.8.0 in which the DSM plugin module, which allows a local authenticated user to achieve local privilege escalation (LPE) on a vulnerable system. The vulnerability has been fixed to allow loading of plugins from the installed directory. Affected users should upgrade their UltraVNC to 1.3.8.1. Users unable to upgrade should not install and run UltraVNC server as a service. It is advisable to create a scheduled task on a low privilege account to launch WinVNC.exe instead. There are no known workarounds if winvnc needs to be started as a service.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
UL
UltraVNC · ultravnc
< 1.3.8.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2022-24750
CVE.org
https://www.cve.org/CVERecord?id=CVE-2022-24750
Patch
https://github.com/bowtiejicode/UltraVNC-DSMPlugin-LPE
Patch
https://github.com/ultravnc/UltraVNC/commit/36a31b37b98f70c1db0428f5ad83170d604fb352
Third Party Advisory
https://github.com/ultravnc/UltraVNC/security/advisories/GHSA-3mvp-cp5x-vj5g
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