CVE-2026-88159

highpriority · track · 36EPSS 0.014 · 73 %ileDEFRUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.44% (73rd) EPSS

CVSS 8.8 · high

Is it mine?

73 products

Check your exposure

Who says so?

3 sources

cert_bund · msrc_csaf · certfr

EPSS · scored 2026-10-27

Use after free in Windows Background Intelligent Transfer Service (BITS) allows an unauthorized attacker to execute code over a network.

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
10.0.14393.9612:Security Update:https://support.microsoft.com/help/5126868
https://support.microsoft.com/help/5126868
FixedWindows 10 Version 1607 for x64-based Systemsmsrc_csaf
10.0.14393.9612:Security Update:https://support.microsoft.com/help/5126868
https://support.microsoft.com/help/5126868
FixedWindows 10 Version 1809 for 32-bit Systemsmsrc_csaf
10.0.17763.9376:Security Update:https://support.microsoft.com/help/5126651
https://support.microsoft.com/help/5126651
FixedWindows 10 Version 1809 for x64-based Systemsmsrc_csaf
10.0.17763.9376:Security Update:https://support.microsoft.com/help/5126651
https://support.microsoft.com/help/5126651
FixedWindows 10 Version 21H2 for 32-bit Systemsmsrc_csaf
10.0.19044.7807:Security Update:https://support.microsoft.com/help/5126657
https://support.microsoft.com/help/5126657
FixedWindows 10 Version 21H2 for ARM64-based Systemsmsrc_csaf
10.0.19044.7807:Security Update:https://support.microsoft.com/help/5126657
https://support.microsoft.com/help/5126657
FixedWindows 10 Version 21H2 for x64-based Systemsmsrc_csaf
10.0.19044.7807:Security Update:https://support.microsoft.com/help/5126657
https://support.microsoft.com/help/5126657
FixedWindows 10 Version 22H2 for 32-bit Systemsmsrc_csaf
10.0.19045.7807:Security Update:https://support.microsoft.com/help/5126657
https://support.microsoft.com/help/5126657
FixedWindows 10 Version 22H2 for ARM64-based Systemsmsrc_csaf
10.0.19045.7807:Security Update:https://support.microsoft.com/help/5126657
https://support.microsoft.com/help/5126657
FixedWindows 10 Version 22H2 for x64-based Systemsmsrc_csaf
10.0.19045.7807:Security Update:https://support.microsoft.com/help/5126657
https://support.microsoft.com/help/5126657
FixedWindows 11 Version 23H2 for ARM64-based Systemsmsrc_csaf
10.0.22631.7652:Security Update:https://support.microsoft.com/help/5126653
https://support.microsoft.com/help/5126653
FixedWindows 11 Version 23H2 for x64-based Systemsmsrc_csaf
10.0.22631.7652:Security Update:https://support.microsoft.com/help/5126653
https://support.microsoft.com/help/5126653
FixedWindows 11 Version 24H2 for ARM64-based Systemsmsrc_csaf
10.0.26100.9711:Security Update:https://support.microsoft.com/help/5127648
https://support.microsoft.com/help/5127648
FixedWindows 11 Version 24H2 for x64-based Systemsmsrc_csaf
10.0.26100.9711:Security Update:https://support.microsoft.com/help/5127648
https://support.microsoft.com/help/5127648
FixedWindows 11 Version 25H2 for ARM64-based Systemsmsrc_csaf
10.0.26200.9711:Security Update:https://support.microsoft.com/help/5127648
https://support.microsoft.com/help/5127648
FixedWindows 11 Version 25H2 for x64-based Systemsmsrc_csaf
10.0.26200.9711:Security Update:https://support.microsoft.com/help/5127648
https://support.microsoft.com/help/5127648
FixedWindows 11 Version 26H1 for ARM64-based Systemsmsrc_csaf
10.0.28000.3231:Security Update:https://support.microsoft.com/help/5127646
https://support.microsoft.com/help/5127646
FixedWindows 11 Version 26H2 for ARM64-based Systemsmsrc_csaf
10.0.26300.9711:Security Update:https://support.microsoft.com/help/5127648
https://support.microsoft.com/help/5127648
FixedWindows 11 Version 26H2 for x64-based Systemsmsrc_csaf
10.0.26300.9711:Security Update:https://support.microsoft.com/help/5127648
https://support.microsoft.com/help/5127648
FixedWindows 11 version 26H1 for x64-based Systemsmsrc_csaf
10.0.28000.3231:Security Update:https://support.microsoft.com/help/5127646
https://support.microsoft.com/help/5127646
FixedWindows Server 2012msrc_csaf
6.2.9200.26434:Security Update:https://support.microsoft.com/help/5126835
https://support.microsoft.com/help/5126835
FixedWindows Server 2012 (Server Core installation)msrc_csaf
6.2.9200.26434:Security Update:https://support.microsoft.com/help/5126835
https://support.microsoft.com/help/5126835
FixedWindows Server 2012 R2msrc_csaf
6.3.9600.23470:Security Update:https://support.microsoft.com/help/5126836
https://support.microsoft.com/help/5126836
FixedWindows Server 2012 R2 (Server Core installation)msrc_csaf
6.3.9600.23470:Security Update:https://support.microsoft.com/help/5126836
https://support.microsoft.com/help/5126836
FixedWindows Server 2016msrc_csaf
10.0.14393.9612:Security Update:https://support.microsoft.com/help/5126868
https://support.microsoft.com/help/5126868
FixedWindows Server 2016 (Server Core installation)msrc_csaf
10.0.14393.9612:Security Update:https://support.microsoft.com/help/5126868
https://support.microsoft.com/help/5126868
FixedWindows Server 2019msrc_csaf
10.0.17763.9376:Security Update:https://support.microsoft.com/help/5126651
https://support.microsoft.com/help/5126651
FixedWindows Server 2019 (Server Core installation)msrc_csaf
10.0.17763.9376:Security Update:https://support.microsoft.com/help/5126651
https://support.microsoft.com/help/5126651
FixedWindows Server 2022msrc_csaf
10.0.20348.5761:Security Update:https://support.microsoft.com/help/5126655
https://support.microsoft.com/help/5126655
FixedWindows Server 2022 (Server Core installation)msrc_csaf
10.0.20348.5761:Security Update:https://support.microsoft.com/help/5126655
https://support.microsoft.com/help/5126655
FixedWindows Server 2025msrc_csaf
10.0.26100.33650:Security Update:https://support.microsoft.com/help/5126646
https://support.microsoft.com/help/5126646
FixedWindows Server 2025 (Server Core installation)msrc_csaf
10.0.26100.33650:Security Update:https://support.microsoft.com/help/5126646
https://support.microsoft.com/help/5126646

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

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · secure@microsoft.com USexploitability 2.8 · impact 5.9

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.18.8highCVSS:3.1/AV:N/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

ssvc

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

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125USCWE-125USCWE-125US

affected products (73)

Products and version ranges known to be affected.

Microsoft Windows 10all versionscert_bundDEcpe:/o:microsoft:windows_10:-
Microsoft Windows 11all versionscert_bundDEcpe:/o:microsoft:windows_11:-
Microsoft Windows Security Appall versionscert_bundDEcpe:/o:microsoft:windows:security_app
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 2025all versionscert_bundDEcpe:/o:microsoft:windows_server_2025:-
Microsoft Windows 10 Version 1607 for 32-bit Systemsall versionsfixedmsrc_csafUS
Microsoft Windows 10 Version 1607 for 32-bit Systems< 10.0.14393.9612msrc_csafUS
Microsoft Windows 10 Version 1607 for x64-based Systemsall versionsfixedmsrc_csafUS
Microsoft Windows 10 Version 1607 for x64-based Systems< 10.0.14393.9612msrc_csafUS
Microsoft Windows 10 Version 1809 for 32-bit Systemsall versionsfixedmsrc_csafUS
Microsoft Windows 10 Version 1809 for 32-bit Systems< 10.0.17763.9376msrc_csafUS
Microsoft Windows 10 Version 1809 for x64-based Systemsall versionsfixedmsrc_csafUS
Microsoft Windows 10 Version 1809 for x64-based Systems< 10.0.17763.9376msrc_csafUS
Microsoft Windows 10 Version 21H2 for 32-bit Systemsall versionsfixedmsrc_csafUS
Microsoft Windows 10 Version 21H2 for 32-bit Systems< 10.0.19044.7807msrc_csafUS
Microsoft Windows 10 Version 21H2 for ARM64-based Systemsall versionsfixedmsrc_csafUS

showing 20 of 73

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-3892Microsoft Windows und Windows Server: Mehrere SchwachstellenDeutsch2026-10-13csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in verschiedenen Versionen von Microsoft Windows Server und Microsoft Windows ausnutzen, um seine Privilegien auf administrative Rechte zu erhöhen, um beliebigen Code auszuführen, um Informationen offenzulegen, um einen Denial of Service herbeizuführen, um den Benutzer zu täuschen und andere, nicht näher spezifizierte Auswirkungen zu verursachen.
msrc_CVE-2026-88159Windows Background Intelligent Transfer Service (BITS) Remote Code Execution Vulnerability2026-10-13csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
CERTFR-2026-AVI-1314Multiples vulnérabilités dans Microsoft WindowsFrançais2026-10-14vendor · certfrFR

sources

Which sources assert this record, and when.

cert_bund msrc_csaf certfr NVD CVE.org MITRE

published 2026-10-13modified 2026-10-16

references (1) nvd

External citations — patches, advisories, analysis.

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88159

scry

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