Vulnerability

CVE-2025-21391

High· 7.1KEVCVSS7.1EPSS5%

.rules3/5

Microsoft Windows Storage Link Following Vulnerability

Microsoft Windows Storage contains a link following vulnerability that could allow for privilege escalation. This vulnerability could allow an attacker to delete data including data that results in the service being unavailable.

Threat signal

86/100

High

Severity

high

CVSS

7.1

EPSS

Active

KEV

CISA KEV — actively exploited

466d overdue

AffectedMicrosoft — Windows

Added to KEV

2025-02-11

Federal patch due (BOD 22-01)

2025-03-04

Required action (CISA verbatim)

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Vendor advisory + references

CISA description: “Microsoft Windows Storage contains a link following vulnerability that could allow for privilege escalation. This vulnerability could allow an attacker to delete data including data that results in the service being unavailable.”

CVSS

v3.1Open in FIRST calculator →

7.1/ 10HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/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 ImpactHighTotal compromise of integrity — full data modification possible.
Availability ImpactHighTotal loss of availability — full DoS possible.

EPSS

Exploit prediction · 30-day horizonFIRST.org →

4.72%

probability of exploitation in next 30 days

p90

higher than 90% of all CVEs

3-day trend↓ 0.4pp

Mid-pack — moderate exploitation likelihood.

Vendor VEX

No VEX statements published for CVE-2025-21391. Vendors publish VEX (Vulnerability Exploitability eXchange) to assert per-product whether a CVE is actually exploitable in their distribution.

SSVCAct

Active exploitation with total impact on essential/support systems

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

Lifecycle

2025-02-11Added to CISA KEVransomware: Unknown
2025-02-11Published
2025-03-04Federal patch due (BOD 22-01)
2026-06-12Last modified1 source

No source-event history recorded yet. New revisions will appear here as ingestors re-fetch this CVE.