Actively exploited

CVE-2023-41763 Microsoft Skype for Business Privilege Escalation Vulnerability

Microsoft Skype for Business contains an unspecified vulnerability that allows for privilege escalation.

From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.

Our Assessment

Should You Worry?

Patch urgentlyCybergen assessment
  • CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 10 Oct 2023.
  • Rated Medium severity (CVSS 5.3, scored by Vendor).
  • It has been in the catalogue for 1,123 days. Systems still unpatched now have almost certainly been scanned for it.
The Vulnerability

What It Is

Skype for Business Elevation of Privilege Vulnerability

Affected Versions

ProductVersions
Microsoft Skype for Business Server 2015 CU139319.0 to before 6.0.9319.869
Microsoft Skype for Business Server 2019 CU72046.0 to before 7.0.246.530

From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.

From Watch to Action

What To Do Now

  1. 1

    Find it

    Search your asset inventory and external attack surface for Microsoft Skype for Business. Include cloud images, appliances and anything a supplier runs for you.

    Attack Surface Management
  2. 2

    Fix it

    Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

    Vulnerability Management
  3. 3

    Hunt for compromise

    If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.

    Incident Response
  4. 4

    Prove it is fixed

    Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.

    Penetration Testing

Not Sure If You Are Exposed?

Our attack surface and vulnerability teams can check your internet-facing estate for CVE-2023-41763 and every other exploited flaw on the list.

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