CVE-2019-18988: in the CISA KEV catalogue

TeamViewer Desktop Bypass Remote Login Vulnerability. CISA added CVE-2019-18988 to the Known Exploited Vulnerabilities catalogue on 2021-11-03 with a default due date of 2022-05-03. Known ransomware campaign use: Unknown. Forensic triage flag: No.

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). (CISA description)

Vendor / product: TeamViewer Desktop
CWE: CWE-521
CISA required action: Apply updates per vendor instructions.
EPSS: 4.7%, percentile 91 (scored 2026-11-03)

EPSS puts about 4.7 in 100 odds (4.7%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 91% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.

Vendor and reference links (from CISA)

https://nvd.nist.gov/vuln/detail/CVE-2019-18988

Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.

Data dates. CISA KEV catalogue version 2026.11.03, released 2026-11-03, 1,767 entries (checked 2026-11-03). EPSS model v2026.06.15, scored 2026-11-03, 399,388 CVEs. Sources: CISA and FIRST (EPSS by FIRST; scores generated by Empirical Security). Copied to our own database and refreshed automatically; if a refresh fails, the previous copy keeps serving with its own date.

Frequently asked questions

Is CVE-2019-18988 in the CISA KEV catalogue?

Yes. CISA added CVE-2019-18988 (TeamViewer Desktop Bypass Remote Login Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2021-11-03. CISA's default due date for it is 2022-05-03.

Is CVE-2019-18988 used in ransomware attacks?

CISA marks known ransomware campaign use as Unknown for CVE-2019-18988. That means CISA lacks confirmation, not that ransomware groups do not use it.

What should I do about CVE-2019-18988?

CISA's required action: Apply updates per vendor instructions.

Sources

CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
NVD record for CVE-2019-18988