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
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-347
- Affected
- microsoft/asp.net core
- Source
- secure@microsoft.com
EPSS moved from 0.8% on 24 September 2026 to 11.2% on 30 October 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.