Threats / Microsoft / CVE-2026-41091
CVE-2026-41091
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Microsoft Defender vulnerability
Microsoft Defender contains a link following vulnerability (CWE-59) allowing authorized attackers to elevate privileges locally.
Verdict
Today item — known-exploited.
An authenticated local attacker can exploit improper link resolution in Microsoft Defender to gain elevated system privileges. The vulnerability has been observed in active exploitation.
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
3 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-05-20).
Probability (EPSS)
EPSS 0.01172 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Defender. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-59 Link Following — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a symbolic or hard link in a location where Defender processes files with elevated privileges.
Business
An insider or compromised local account gains system-level access, bypassing security boundaries.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I direct Defender's file operations to follow my malicious link to a sensitive system location.
Business
Defender's elevated context is abused to modify protected files or registry entries.
3
Lateral reach — past segmentation narrative 3
Attacker
I achieve code execution or configuration changes running under SYSTEM or Administrator privileges.
Business
Endpoint security controls are compromised, enabling lateral movement, persistence, or data exfiltration.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05