CVE-2026-21242Disclosure(microsoft / windows_10_21h2)

LOWCVSS 7.0 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD description

Use after free in Windows Subsystem for Linux allows an authorized attacker to elevate privileges locally.

microsoft CVEs Back to dashboard

0.5/ 10 priority

Sources & remediation

Vendor / third-party advisories

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21242

Weakness type (CWE)

CWE-416

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

NONE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

windows_10_21h2
windows_10_22h2
windows_11_23h2
windows_11_24h2

Threat summary

1 mentions across 1 observed day

What's happening

Technical details provided in 1 signal
Disclosure: 1 classified signal
1 total mentions across 1 day

Affected systems

Vendors

microsoft

Products

windows_10_21h2windows_10_22h2windows_11_23h2windows_11_24h2windows_11_25h2windows_server_2022windows_server_2022_23h2windows_server_2025

Deep dive

Activity timeline1 mentions / 1d

Signal classification1 categories

Disclosure

1100.0%

Referenced assets1 URL

By indicator

https://www.cve.org/CVERecord?id=CVE-2026-21242

Full discourse1 post

CVE@CVEnew241d
Disclosure
CVE-2026-21242 Use after free in Windows Subsystem for Linux allows an authorized attacker to elevate privileges locally. https://www.cve.org/CVERecord?id=CVE-2026-21242
Post summary
The text announces a use‑after‑free vulnerability in Windows Subsystem for Linux that allows local privilege escalation, with no evidence of PoC, exploit, patch, or active exploitation.
00000168
56.5K followersView on X

CPE platform detail13 entries

Part:

Vendor:

Product:

Version:

Target SW:

Target HW:

13 of 13 entries

Part	Vendor	Product	Version	Target SW	Target HW
OS	microsoft	windows_10_21h2	-	-	arm64
OS	microsoft	windows_10_21h2	-	-	x64
OS	microsoft	windows_10_22h2	-	-	arm64
OS	microsoft	windows_10_22h2	-	-	x64
OS	microsoft	windows_11_23h2	-	-	arm64
OS	microsoft	windows_11_23h2	-	-	x64
OS	microsoft	windows_11_24h2	-	-	arm64
OS	microsoft	windows_11_24h2	-	-	x64
OS	microsoft	windows_11_25h2	-	-	arm64
OS	microsoft	windows_11_25h2	-	-	x64
OS	microsoft	windows_server_2022	-	-	-
OS	microsoft	windows_server_2022_23h2	-	-	-
OS	microsoft	windows_server_2025	-	-	-

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