TeamViewer Full Client and Host: Local privilege escalation via TOCTOU race condition
Summary
A time-of-check time-of-use race condition combined with improper symbolic link handling in the privileged helper of TeamViewer Full Client and Host for macOS allows a local attacker to bypass installer package verification and install a malicious package. Successful exploitation leads to local privilege escalation to root. The attacker needs low privileges and a local account on the affected Mac; no user interaction is required.
Affected
- TeamViewer Full Client for macOS prior to 15.83
- TeamViewer Host for macOS prior to 15.83
- Legacy branches: Full Client and Host 14.7 for macOS before 14.7.48868, 13.2 for macOS before 13.2.154007
Fixed in
- TeamViewer Full Client and Host 15.83 or later for macOS
- Host 14.7.48868 and Host 13.2.154007 for macOS (legacy)
- Full Client legacy fixed build for macOS 14.7 and 13.2: Unknown (not listed in the vendor bulletin; check the bulletin directly)
Workaround
Unknown. The vendor documents no workaround; the fixed versions should be applied.
Exploitation
- TeamViewer is not aware of active exploitation at the time of publication.
- CISA KEV status: Unknown (not verified directly).
- No public proof of concept known at the time of research.
- EPSS: 0.09 % (percentile 0).
Our recommendation
- Inventory all macOS endpoints with TeamViewer Full Client or Host and update them to 15.83 or later.
- Verify legacy builds against the vendor bulletin before any rollout.
- Prioritise shared, multi-user or unattended Macs and restrict local accounts where possible.
- Patch CVE-2026-111585 and CVE-2026-92372 at the same time, as they can be triggered remotely.
- Re-check the vendor bulletin and CISA KEV for changes.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- TeamViewer Security Bulletin TV-2026-1011 www.teamviewer.com
- CVE-2026-92374 record (threatint) cve.threatint.com
- CVE-2026-92374 overview (Strix) www.strix.ai
- CyberSecurityNews: TeamViewer desktop session vulnerabilities cybersecuritynews.com
- Heise: TeamViewer fixes code injection vulnerability www.heise.de
- CWE-367 TOCTOU race condition (vuln.today) vuln.today
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 22:12.
Original description (NVD)
A time-of-check time-of-use (TOCTOU) race condition combined with improper symbolic link handling in the privileged helper of TeamViewer Full Client and Host prior to version 15.83 for macOS allows a local attacker with low privileges to bypass installer package verification and install a malicious package. Successful exploitation can lead to local privilege escalation to root.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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