What is CVE-2025-64656?

CVE-2025-64656 is a critical-severity vulnerability in Microsoft Azure App Gateway, classified under Out-of-bounds Read. CVSS score: 9.4/10. Published 2025-11-26.

How severe is CVE-2025-64656?

Critical severity. CVSS v3 base score is 9.4 out of 10.

Out-of-bounds Read in Microsoft Azure App Gateway

CVE-2025-64656

Out-of-bounds read in Application Gateway allows an unauthorized attacker to elevate privileges over a network.

Vulnerability class: Buffer Overflow

Published 2025-11-26 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.4 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L.

EPSS exploit prediction

EPSS: 0.006 (47.9th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 48th percentile — 47.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2025-64656 (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2025-64656?: CVE-2025-64656 is a critical-severity vulnerability in Microsoft Azure App Gateway, classified under Out-of-bounds Read. CVSS score: 9.4/10. Published 2025-11-26.
How severe is CVE-2025-64656?: Critical severity. CVSS v3 base score is 9.4 out of 10.