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

Vulnerability from cvelistv5 – Published: 2026-05-20 13:09 – Updated: 2026-06-19 16:13
VLAI CISA KEVIntel
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
SSVC
Exploitation: active Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
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
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
KEVIntel
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: f7a5751d-4514-43a7-bcb7-3c139a42edbd

Vulnerability ID: CVE-2026-41091

Status: Confirmed

Status Updated: 2026-06-01 13:29 UTC

Exploited: Yes

Timestamps
First Seen: 2026-06-01
Asserted: 2026-06-01
Scope
Notes: KEVIntel entry: Microsoft Defender Elevation of Privilege Vulnerability | Affected: Microsoft / Microsoft Malware Protection Engine | CVSS: 7.8 (HIGH) | EPSS: 0.01172 | Used in malware: unknown | Not yet in CISA KEV: False
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: kevintel

Details
Feed KEVIntel (kevintel.com)
Title Microsoft Defender Elevation of Privilege Vulnerability
Vendor Microsoft
Product Microsoft Malware Protection Engine
Added Date 2026-06-01T13:29:26.114Z
Cvss Score 7.8
Epss Score 0.01172
Cvss Severity HIGH
Epss Percentile 0.63371
Used In Malware unknown
Ahead Of Cisa Kev 
{
  "count": 1,
  "unit": "day"
}
Not Yet In Cisa Kev False
References
Created: 2026-06-23 14:03 UTC | Updated: 2026-06-23 14:03 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.