Vulnerability

CVE-2021-41379

Medium· 5.5KEVCVSS5.5EPSS19%

.rules3/5

Windows Installer Elevation of Privilege Vulnerability

Threat signal

68/100

Elevated

Severity

medium

CVSS

5.5

EPSS

19%

Active

KEV

CISA KEV — actively exploited

Ransomware: Known1674d overdue

AffectedMicrosoft — Windows

Added to KEV

2022-03-03

Federal patch due (BOD 22-01)

2022-03-17

Required action (CISA verbatim)

Apply updates per vendor instructions.

Vendor advisory + references

https://nvd.nist.gov/vuln/detail/CVE-2021-41379

CISA description: “Microsoft Windows Installer contains an unspecified vulnerability that allows for privilege escalation.”

CVSS

v3.1via NVDOpen in FIRST calculator →

5.5/ 10MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack VectorLocalRequires local access — shell, console, or local app.
Attack ComplexityLowNo special conditions — exploit works reliably.
Privileges RequiredLowStandard user privileges sufficient.
User InteractionNoneFully automated — no victim action needed.
ScopeUnchangedImpact contained to the vulnerable component.
Confidentiality ImpactNoneNo confidentiality impact.
Integrity ImpactNoneNo integrity impact.
Availability ImpactHighTotal loss of availability — full DoS possible.

EPSS

Exploit prediction · 30-day horizonFIRST.org →

19.4%

probability of exploitation in next 30 days

p97

higher than 97% of all CVEs

3-day trend↑ 0pp

Above the FIRST 'patch on a priority schedule' threshold.

Vendor VEX

No VEX statements published for CVE-2021-41379. Vendors publish VEX (Vulnerability Exploitability eXchange) to assert per-product whether a CVE is actually exploitable in their distribution.

SSVCAttend

Active exploitation with limited impact — coordinate patching

exploitation: active
automatable: no
impact: partial
mission: support

Lifecycle

2021-11-10Published
2022-03-03Added to CISA KEVransomware: Known
2022-03-17Federal patch due (BOD 22-01)
2026-08-19Last modified2 sources

CVE-2021-41379

CISA KEV — actively exploited

CVSS

EPSS

Vendor VEX

Lifecycle

References

CVE-2021-41379

CISA KEV — actively exploited

CVSS

EPSS

Vendor VEX

Lifecycle

References