CVE-2023-3181: Splashtop Software Updater · Creation of Temporary File in Directory with Insecure Permissions
Affects Splashtop Software UpdaterSource CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 09:15 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jan 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Splashtop Splashtop Software Updater | Affected
| Fixed in– |
AI-suggested
1. Immediate mitigation should include restricting write permissions to the C:\Windows\Temp directory and its subdirectories to prevent standard users from placing malicious DLLs. 2. Implement application whitelisting or code integrity policies (e.g., Windows Defender Application Control) to prevent unauthorized DLLs from loading in the Splashtop updater directory. 3. Monitor and audit the creation and modification of files within C:\Windows\Temp~nsu.tmp and related directories to detect suspicious activity. 4. Where possible, run Splashtop Software Updater and related processes with the least privileges necessary, avoiding SYSTEM-level execution unless absolutely required. 5. 6. Educate users and administrators about the risks of privilege escalation and the importance of maintaining strict file system permissions. 7. Employ endpoint detection and response (EDR) solutions to detect DLL hijacking attempts and anomalous process launches involving Au_.exe or similar executables.
Description
The C:\Program Files (x86)\Splashtop\Splashtop Software Updater\uninst.exe process creates a folder at C:\Windows\Temp~nsu.tmp and copies itself to it as Au_.exe. The C:\Windows\Temp~nsu.tmp\Au_.exe file is automatically launched as SYSTEM when the system reboots or when a standard user runs an MSI repair using Splashtop Streamer’s Windows Installer. Since the C:\Windows\Temp~nsu.tmp folder inherits permissions from C:\Windows\Temp and Au_.exe is susceptible to DLL hijacking, standard users can write a malicious DLL to it and elevate their privileges.