CVE-2021-47890
Privilege escalation via unquoted LogonExpertSvc path on Windows.
Is CVE-2021-47890 being exploited?
Not confirmed. CVE-2021-47890 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.13% probability of exploitation in the next 30 days.
How severe is CVE-2021-47890?
CVE-2021-47890 is rated High with a CVSS score of 8.5. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2021-47890?
Not known from our data. No patch reference has been recorded for CVE-2021-47890, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2021-47890 affect?
CVE-2021-47890 affects LogonExpert 8.1, Windows with LogonExpertSvc. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2021-47890?
Apply vendor fix when available; monitor service startup and path quoting.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unquoted service path enables LocalSystem privilege escalation during startup.
Patch when possible
- affected8.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.