Exploited vulnerabilities / CVE-2026-41091
Confirmed exploited · privilege escalation · Microsoft DefenderCVE-2026-41091
Microsoft Defender privilege escalation, confirmed exploited in the wild.
Microsoft Defender contains a link following vulnerability that allows an authorized attacker to elevate privileges locally.
| CISA's name for it | Microsoft Defender Link Following Vulnerability |
|---|---|
| Vendor and product | Microsoft · Defender |
| Type | privilege escalation · CWE-59 |
| Exploited | Confirmed by CISA listed 20 May 2026 |
| Likelihood | more likely to be exploited than most |
| Deadline | 3 June 2026 · already passed |
| Used in ransomware | Not reported |
| Advisories | msrc.microsoft.com ↗ · nvd.nist.gov ↗ |
Three steps, in this order
Install the update on every affected system, servers and workstations alike.
Escalation bugs are chained after a first foothold: check for other exposures an attacker could start from.
Review who holds administrative rights, and alert on new ones.
| CISA's 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. |
|---|
Know before someone else finds it
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CVE-2026-41091 in short
Is CVE-2026-41091 being exploited?
Yes. CISA added CVE-2026-41091 to its Known Exploited Vulnerabilities catalogue on 20 May 2026, which it does only on evidence of exploitation in the wild.
What is the CISA deadline for CVE-2026-41091?
US federal agencies must remediate it by 3 June 2026. Everyone else should treat that date as the latest safe point to patch an internet-facing system.
How likely is CVE-2026-41091 to be exploited in the next 30 days?
FIRST's Exploit Prediction Scoring System gives it 8.2%, the 94th percentile of every CVE it scores.
How do I fix CVE-2026-41091?
Install the update on every affected system, servers and workstations alike. Escalation bugs are chained after a first foothold: check for other exposures an attacker could start from. Review who holds administrative rights, and alert on new ones.
Other Microsoft vulnerabilities being exploited
| CVE | Product | Type | Listed |
|---|---|---|---|
| CVE-2026-124194 | Office | exploited vulnerability | 10 November 2026 |
| CVE-2026-96951 | Windows | command injection | 13 October 2026 |
| CVE-2026-65660 | SharePoint | exploited vulnerability | 25 September 2026 |
| CVE-2026-81963 | Windows | privilege escalation | 8 September 2026 |
| CVE-2026-85880 | Windows | privilege escalation | 8 September 2026 |
| CVE-2019-1068 | SQL Server | remote code execution | 26 August 2026 |
Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.