CVE-2026-21510

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.245 · 98 %ileexploit · PoCDEEUJPNLRUUS
grimoire priorityP0 · Act now
Exploitable?
Yes · in the wild
CISA KEV · 2 exploits · PoC
Likely / severe?
24.5% (98th) EPSS
CVSS 8.8 · high
Is it mine?
193 products
Check your exposure
Who says so?
7 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

added 2026-02-10remediate by 2026-03-03

required action Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

EPSS · scored 2026-10-22

Microsoft Windows Shell Protection Mechanism Failure Vulnerability

Protection mechanism failure in Windows Shell allows an unauthorized attacker to bypass a security feature over a network.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

8.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.18.8highAV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:Csecondary · ENISA EU
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · secure@microsoft.com USexploitability 2.8 · impact 5.9
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:Csecondary · NCSC-NL NL
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:Csecondary · Microsoft Security Response Center US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

05

exploits (2)

Public proof-of-concept and weaponised exploit code.

06

affected products (193)

Products and version ranges known to be affected.

showing 20 of 193
07

advisories (4)

Vendor and ecosystem advisories describing this.

  • NCSC-2026-0053Kwetsbaarheden verholpen in Microsoft WindowsNL2026-02-10csaf · ncsc_nlNL

    Microsoft heeft kwetsbaarheden verholpen in Windows.

  • WID-SEC-W-2026-0369Microsoft Windows: Mehrere SchwachstellenDeutsch2026-02-10csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Microsoft Windows-Produkten ausnutzen, um Administratorrechte zu erlangen, beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, Spoofing-Angriffe zu starten, Daten zu manipulieren, vertrauliche Informationen offenzulegen und einen Denial-of-Service-Zustand zu verursachen.

  • msrc_CVE-2026-21510Windows Shell Security Feature Bypass Vulnerability2026-02-10csaf · msrc_csafUS

    To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

  • JVNDB-2026-009406JVN iPedia advisory JVNDB-2026-0094062026-03-31vendor · jvndbJP
08

also known as (4)

Other names and identifiers for this entity.

09

sources

Which sources assert this record, and when.

10

references (5)

External citations — patches, advisories, analysis.

scry

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