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TI-2026-69823 Aliases CVE-2026-77900

Azure App Service for Linux Unauthenticated Remote Code Execution

Priority MEDIUM 50CWE-306Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-306.

Summary

Missing authentication for a critical function in Azure App Service for Linux, tracked as CWE-306, allows an unauthenticated remote attacker to execute code over the network. Microsoft's listing has a CVSS 3.1 base score of 9.8 (CRITICAL) with network attack vector, low complexity and no privileges or user interaction required. CISA's SSVC data marks the vulnerability as automatable with total technical impact, but reports no known exploitation and CISA has not added it to KEV.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

Missing authentication for critical function in Azure App Service allows an unauthorized attacker to execute code over a network.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0072 54th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftAzure App Service for Linux-—No fix listedCNA
  • Azure App Service for Linux VendorMicrosoft Affected - Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for Azure App Service for Linux at this time. Monitor the Microsoft advisory for CVE-2026-77900 for an update and restrict network access to affected App Service instances until a patch is available.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Timeline

  1. 2026-10-09 Threatist record created from CVE-2026-77900
  2. 2026-10-10 CISA SSVC decision points changed
  3. 2026-10-25 EPSS moved to the 50th–90th percentile

References

Patch 1

  • TI-2026-42212 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-37256 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-16982 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-36863 Windows Server Update Service (WSUS) Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-33671 Microsoft SharePoint Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
See all 18045 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences