CVE-2026-20833

mediumpriority · track · 10OT risk · elevatedEPSS 0.005 · 45 %ileexploit · PoCDEEUNLRUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

2 exploits · PoC

Likely / severe?

0.53% (45th) EPSS

CVSS 5.5 · medium

Is it mine?

152 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

Use of a broken or risky cryptographic algorithm in Windows Kerberos allows an authorized attacker to disclose information locally.

remediations

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

A vendor fix is available.

FixedWindows Server 2008 R2 for x64-based Systems Service Pack 1msrc_csaf
6.1.7601.28117:Monthly Rollup:https://support.microsoft.com/help/5073695
https://support.microsoft.com/help/5073695
FixedWindows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)msrc_csaf
6.1.7601.28117:Monthly Rollup:https://support.microsoft.com/help/5073695
https://support.microsoft.com/help/5073695
FixedWindows Server 2008 for 32-bit Systems Service Pack 2msrc_csaf
6.0.6003.23717:Monthly Rollup:https://support.microsoft.com/help/5073697
https://support.microsoft.com/help/5073697
FixedWindows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)msrc_csaf
6.0.6003.23717:Monthly Rollup:https://support.microsoft.com/help/5073697
https://support.microsoft.com/help/5073697
FixedWindows Server 2008 for x64-based Systems Service Pack 2msrc_csaf
6.0.6003.23717:Monthly Rollup:https://support.microsoft.com/help/5073697
https://support.microsoft.com/help/5073697
FixedWindows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)msrc_csaf
6.0.6003.23717:Monthly Rollup:https://support.microsoft.com/help/5073697
https://support.microsoft.com/help/5073697
FixedWindows Server 2012msrc_csaf
6.2.9200.25868:Monthly Rollup:https://support.microsoft.com/help/5073698
https://support.microsoft.com/help/5073698
FixedWindows Server 2012 (Server Core installation)msrc_csaf
6.2.9200.25868:Monthly Rollup:https://support.microsoft.com/help/5073698
https://support.microsoft.com/help/5073698
FixedWindows Server 2012 R2msrc_csaf
6.3.9600.22968:Monthly Rollup:https://support.microsoft.com/help/5073696
https://support.microsoft.com/help/5073696
FixedWindows Server 2012 R2 (Server Core installation)msrc_csaf
6.3.9600.22968:Monthly Rollup:https://support.microsoft.com/help/5073696
https://support.microsoft.com/help/5073696
FixedWindows Server 2016msrc_csaf
10.0.14393.8783:Security Update:https://support.microsoft.com/help/5073722
https://support.microsoft.com/help/5073722
FixedWindows Server 2016 (Server Core installation)msrc_csaf
10.0.14393.8783:Security Update:https://support.microsoft.com/help/5073722
https://support.microsoft.com/help/5073722
FixedWindows Server 2019msrc_csaf
10.0.17763.8276:Security Update:https://support.microsoft.com/help/5073723
https://support.microsoft.com/help/5073723
FixedWindows Server 2019 (Server Core installation)msrc_csaf
10.0.17763.8276:Security Update:https://support.microsoft.com/help/5073723
https://support.microsoft.com/help/5073723
FixedWindows Server 2022msrc_csaf
10.0.20348.4648:Security Update:https://support.microsoft.com/help/5073457
https://support.microsoft.com/help/5073457
FixedWindows Server 2022 (Server Core installation)msrc_csaf
10.0.20348.4648:Security Update:https://support.microsoft.com/help/5073457
https://support.microsoft.com/help/5073457
FixedWindows Server 2022, 23H2 Edition (Server Core installation)msrc_csaf
10.0.25398.2092:Security Update:https://support.microsoft.com/help/5073450
https://support.microsoft.com/help/5073450
FixedWindows Server 2025msrc_csaf
10.0.26100.32230:Security Update:https://support.microsoft.com/en-us/topic/a6021fd2-b3b7-45a7-b68e-35c28a2a77da
https://support.microsoft.com/en-us/topic/a6021fd2-b3b7-45a7-b68e-35c28a2a77da
FixedWindows Server 2025 (Server Core installation)msrc_csaf
10.0.26100.32230:Security Update:https://support.microsoft.com/en-us/topic/a6021fd2-b3b7-45a7-b68e-35c28a2a77da
https://support.microsoft.com/en-us/topic/a6021fd2-b3b7-45a7-b68e-35c28a2a77da

cvss

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

5.5

010

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

v3.15.5mediumAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · FSTEC (BDU) RU

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:Csecondary · ENISA EU

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Nsecondary · secure@microsoft.com USexploitability 1.8 · impact 3.6

v3.15.2mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:Psecondary · CVSS-BT (t0sche)

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:Csecondary · NCSC-NL NL

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:Csecondary · Microsoft Security Response Center US

ssvc

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

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-327USCWE-327USCWE-327USCWE-327US

exploits (2)

Public proof-of-concept and weaponised exploit code.

AlMarWorld/KerberosAudit-PSKerberos audit for CVE-2026-20833PoC · poc_in_github
v-jfanca/cve-2026-20833-rc4-kerberosKerberos RC4 deprecation: detection, remediation and guidance (CVE-2026-20833)PoC · poc_in_github

affected products (152)

Products and version ranges known to be affected.

Hitachi Storageall versionscert_bundDEcpe:/h:hitachi:storage:-
Microsoft Windows 10 Version 1607all versionscert_bundDEcpe:/o:microsoft:windows_10:version_1607
Microsoft Windows 10 Version 1809all versionscert_bundDEcpe:/o:microsoft:windows_10:version_1809
Microsoft Windows 10 Version 21H2all versionscert_bundDEcpe:/o:microsoft:windows_10:version_21h2
Microsoft Windows 10 Version 22H2all versionscert_bundDEcpe:/o:microsoft:windows_10:version_22h2
Microsoft Windows 11 Version 23H2all versionscert_bundDEcpe:/o:microsoft:windows_11:version_23h2
Microsoft Windows 11 Version 24H2all versionscert_bundDEcpe:/o:microsoft:windows_11:version_24h2
Microsoft Windows 11 Windows Terminalall versionscert_bundDEcpe:/o:microsoft:windows_11:windows_terminal
Microsoft Windows Server 2008 R2 SP1all versionscert_bundDEcpe:/o:microsoft:windows_server:2008_r2_sp1
Microsoft Windows Server 2008 SP2all versionscert_bundDEcpe:/o:microsoft:windows_server:2008_sp2
Microsoft Windows Server 2012all versionscert_bundDEcpe:/o:microsoft:windows_server_2012:-
Microsoft Windows Server 2012 R2all versionscert_bundDEcpe:/o:microsoft:windows_server_2012_r2:-
Microsoft Windows Server 2016all versionscert_bundDEcpe:/o:microsoft:windows_server_2016:-
Microsoft Windows Server 2019all versionscert_bundDEcpe:/o:microsoft:windows_server_2019:-
Microsoft Windows Server 2022all versionscert_bundDEcpe:/o:microsoft:windows_server_2022:-
Microsoft Windows Server 2022 23H2 Editionall versionscert_bundDEcpe:/o:microsoft:windows_server_2022:23h2_edition
Microsoft Windows Server 2025all versionscert_bundDEcpe:/o:microsoft:windows_server_2025:-
Open Source Samba <4.24.0all versionscert_bundDE
Open Source Samba< 4.24.0cert_bundDE
Microsoft Windows Server 2008 R2 Service Pack 16.1.7601.0 → 6.1.7601.28117enisa_euvdEU

showing 20 of 152

advisories (4)

Vendor and ecosystem advisories describing this.

NCSC-2026-0007Kwetsbaarheden verholpen in Microsoft WindowsNL2026-01-13csaf · ncsc_nlNL
Microsoft heeft kwetsbaarheden verholpen in Windows
WID-SEC-W-2026-0083Microsoft Windows : Mehrere SchwachstellenDeutsch2026-01-13csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in verschiedenen Versionen von Microsoft Windows und Microsoft Windows Server ausnutzen,, um erweiterte Privilegien, einschließlich Benutzer- und Administratorrechten, zu erlangen, beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, einen Denial-of-Service-Zustand zu verursachen und Daten zu manipulieren.
WID-SEC-W-2026-0780Samba: Schwachstelle ermöglicht Offenlegung von InformationenDeutsch2026-03-18csaf · cert_bundDE
Ein lokaler Angreifer kann eine Schwachstelle in Samba ausnutzen, um Informationen offenzulegen.
msrc_CVE-2026-20833Windows Kerberos Information Disclosure Vulnerability2026-01-13csaf · 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 cert_bund ncsc_nl msrc_csaf NVD CVE.org MITRE

published 2026-01-13modified 2026-06-17

references (3)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

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