Critical severity · published Oct 8, 2026
CVE-2026-77900
Azure App Service Remote Code Execution Vulnerability
9.8
CVSS
0.7%
EPSS
No
On KEV
Description
Missing authentication for critical function in Azure App Service allows an unauthorized attacker to execute code over a network.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AA
Azure App Service for Linux · Microsoft
All versions, or not specified · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77900
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77900
vendor-advisory
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-77900
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