CVE-2026-41091 (GCVE-0-2026-41091)

Vulnerability from cvelistv5 – Published: 2026-05-20 13:09 – Updated: 2026-05-26 16:57
VLAI CISA KEV
Title
Microsoft Defender Elevation of Privilege Vulnerability
Summary
Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
Assigner
References
Impacted products
Vendor Product Version
Microsoft Microsoft Malware Protection Engine Affected: 1.1.0.0 , < 1.1.26040.8 (custom)
Create a notification for this product.
Date Public
2026-05-19 14:00
CISA KEV
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 585a485a-b1a5-49e8-8e94-9e2a71a3efb4

Vulnerability ID: CVE-2026-41091

Status: Confirmed

Status Updated: 2026-05-20 00:00 UTC

Exploited: Yes

Timestamps
First Seen: 2026-05-20
Asserted: 2026-05-20
Scope
Notes: KEV entry: Microsoft Defender Link Following Vulnerability | Affected: Microsoft / Defender | Description: Microsoft Defender contains a link following vulnerability that allows an authorized attacker to elevate privileges locally. | Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. | Due date: 2026-06-03 | Known ransomware campaign use (KEV): Unknown | Notes (KEV): https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-41091 ; https://nvd.nist.gov/vuln/detail/CVE-2026-41091
Evidence

Type: Vendor Report

Signal: Successful Exploitation

Confidence: 80%

Source: cisa-kev

Details
Cwes CWE-59
Feed CISA Known Exploited Vulnerabilities Catalog
Product Defender
Due Date 2026-06-03
Date Added 2026-05-20
Vendorproject Microsoft
Vulnerabilityname Microsoft Defender Link Following Vulnerability
Knownransomwarecampaignuse Unknown
References
Created: 2026-05-20 18:00 UTC | Updated: 2026-05-20 18:00 UTC
Show details on NVD website
To clipboard 

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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.