CVE-2021-26871

mediumpriority · track · 29EPSS 0.014 · 73 %ileexploit · PoCEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

1.43% (73rd) EPSS

CVSS 4.6 · medium

Is it mine?

57 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · msrc_csaf

EPSS · scored 2026-10-27

Windows WalletService Elevation of Privilege Vulnerability

remediations

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

A vendor fix is available.

FixedWindows 10 Version 1607 for 32-bit Systemsmsrc_csaf
10.0.14393.4283:Security Update:https://support.microsoft.com/help/5000803
https://support.microsoft.com/help/5000803
FixedWindows 10 Version 1607 for x64-based Systemsmsrc_csaf
10.0.14393.4283:Security Update:https://support.microsoft.com/help/5000803
https://support.microsoft.com/help/5000803
FixedWindows 10 Version 1803 for 32-bit Systemsmsrc_csaf
10.0.17134.2087:Security Update:https://support.microsoft.com/help/5000809
https://support.microsoft.com/help/5000809
FixedWindows 10 Version 1803 for ARM64-based Systemsmsrc_csaf
10.0.17134.2087:Security Update:https://support.microsoft.com/help/5000809
https://support.microsoft.com/help/5000809
FixedWindows 10 Version 1803 for x64-based Systemsmsrc_csaf
10.0.17134.2087:Security Update:https://support.microsoft.com/help/5000809
https://support.microsoft.com/help/5000809
FixedWindows 10 Version 1809 for 32-bit Systemsmsrc_csaf
10.0.17763.1817:Security Update:https://support.microsoft.com/help/5000822
https://support.microsoft.com/help/5000822
FixedWindows 10 Version 1809 for ARM64-based Systemsmsrc_csaf
10.0.17763.1817:Security Update:https://support.microsoft.com/help/5000822
https://support.microsoft.com/help/5000822
FixedWindows 10 Version 1809 for x64-based Systemsmsrc_csaf
10.0.17763.1817:Security Update:https://support.microsoft.com/help/5000822
https://support.microsoft.com/help/5000822
FixedWindows 10 Version 1909 for 32-bit Systemsmsrc_csaf
10.0.18363.1440:Security Update:https://support.microsoft.com/help/5000808
https://support.microsoft.com/help/5000808
FixedWindows 10 Version 1909 for ARM64-based Systemsmsrc_csaf
10.0.18363.1440:Security Update:https://support.microsoft.com/help/5000808
https://support.microsoft.com/help/5000808
FixedWindows 10 Version 1909 for x64-based Systemsmsrc_csaf
10.0.18363.1440:Security Update:https://support.microsoft.com/help/5000808
https://support.microsoft.com/help/5000808
FixedWindows 10 Version 2004 for 32-bit Systemsmsrc_csaf
10.0.19043.867:Security Update:https://support.microsoft.com/help/5000802
https://support.microsoft.com/help/5000802
FixedWindows 10 Version 2004 for ARM64-based Systemsmsrc_csaf
10.0.19043.867:Security Update:https://support.microsoft.com/help/5000802
https://support.microsoft.com/help/5000802
FixedWindows 10 Version 2004 for x64-based Systemsmsrc_csaf
10.0.19043.867:Security Update:https://support.microsoft.com/help/5000802
https://support.microsoft.com/help/5000802
FixedWindows 10 Version 20H2 for 32-bit Systemsmsrc_csaf
10.0.19043.867:Security Update:https://support.microsoft.com/help/5000802
https://support.microsoft.com/help/5000802
FixedWindows 10 Version 20H2 for ARM64-based Systemsmsrc_csaf
10.0.19043.867:Security Update:https://support.microsoft.com/help/5000802
https://support.microsoft.com/help/5000802
FixedWindows 10 for 32-bit Systemsmsrc_csaf
10.0.10240.18874:Security Update:https://support.microsoft.com/help/5000807
https://support.microsoft.com/help/5000807
FixedWindows 10 for x64-based Systemsmsrc_csaf
10.0.10240.18874:Security Update:https://support.microsoft.com/help/5000807
https://support.microsoft.com/help/5000807

cvss

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

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.1–7.8

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.9 · impact 6.4

v2.04.1mediumAV:L/AC:L/Au:N/C:P/I:P/A:P/E:POCsecondary · CVSS-BT (t0sche)

v3.17.8highAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · secure@microsoft.com USexploitability 1.8 · impact 5.9

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · Microsoft Security Response Center US

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · ENISA EU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · NVD / NIST USexploitability 1.8 · impact 5.9

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-269US

exploits (1)

Public proof-of-concept and weaponised exploit code.

fr4nkxixi/CVE-2021-26871_POCPOC for CVE-2021-26871(Maybe)PoC · poc_in_github

affected products (57)

Products and version ranges known to be affected.

Microsoft Windows 10 Version 150710.0.0 → publicationenisa_euvdEU
Microsoft Windows 10 Version 160710.0.0 → publicationenisa_euvdEU
Microsoft Windows 10 Version 180310.0.0 → publicationenisa_euvdEU
Microsoft Windows 10 Version 180910.0.0 → publicationenisa_euvdEU
Microsoft Windows 10 Version 190910.0.0 → publicationenisa_euvdEU
Microsoft Windows 10 Version 200410.0.0 → publicationenisa_euvdEU
Microsoft Windows 10 Version 20H210.0.0 → publicationenisa_euvdEU
Microsoft Corp Windows 10all versionsfstec_bduRU
Microsoft Corp Windows 10 1607all versionsfstec_bduRU
Microsoft Corp Windows 10 1803all versionsfstec_bduRU
Microsoft Corp Windows 10 1809all versionsfstec_bduRU
Microsoft Corp Windows 10 1909all versionsfstec_bduRU
Microsoft Corp Windows 10 2004all versionsfstec_bduRU
Microsoft Corp Windows 10 20H2all versionsfstec_bduRU
Windows 10 Version 1607 for 32-bit Systemsall versionsfixedmsrc_csafUS
Windows 10 Version 1607 for 32-bit Systems< 10.0.14393.4283msrc_csafUS
Windows 10 Version 1607 for x64-based Systemsall versionsfixedmsrc_csafUS
Windows 10 Version 1607 for x64-based Systems< 10.0.14393.4283msrc_csafUS
Windows 10 Version 1803 for 32-bit Systemsall versionsfixedmsrc_csafUS
Windows 10 Version 1803 for 32-bit Systems< 10.0.17134.2087msrc_csafUS

showing 20 of 57

advisories (1)

Vendor and ecosystem advisories describing this.

msrc_CVE-2021-26871Windows WalletService Elevation of Privilege Vulnerability2021-03-09csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu msrc_csaf NVD CVE.org MITRE

published 2021-03-11modified 2026-08-19

references (6)

External citations — patches, advisories, analysis.

scry

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