Known exploited · TeamViewer
CVE-2019-18988: TeamViewer Desktop Bypass Remote Login Vulnerability
What it is
TeamViewer Desktop allows for bypass of remote-login access control because the same AES key is used for different customers' installations. If an attacker were to know this key, they could decrypt protected information stored in registry or configuration files or decryption of the Unattended Access password to the system (which allows for remote login to the system).
- Vendor
- TeamViewer
- Product
- Desktop
- Added to KEV
- November 3, 2021
- CISA due date
- May 3, 2022
- Ransomware use
- Unknown
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of Desktop you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before May 3, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.