CVE-2026-77900

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

Scores

CVSS out of 10, critical severity.

EPSS chance of exploitation in the next 30 days.

Published

8 October 2026

Last changed

10 October 2026

NVD status

Awaiting Analysis

Severity

Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness

Known exploited

Not in the CISA Known Exploited Vulnerabilities catalogue in this build.

EPSS

0.5% chance of exploitation activity in the next 30 days (percentile 41).

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