SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-40372

Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network.

CRITICAL 9.1EPSS 11.2%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 11.2%, higher than 96% of all known CVEs. Patch or mitigate before the next change window.

Description

Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network.

CVSS 3.1
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS
11.21% probability · 96th percentile
CISA KEV
Not listed
Weakness
CWE-347
Affected
microsoft/asp.net core
Source
secure@microsoft.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.