Vulnerability · Published Apr 21, 2026 · Assigned by microsoft
CVE-2026-40372ASP.NET Core Elevation of Privilege Vulnerability
Critical 9.1
In plain English
A critical-severity security flaw in ASP.NET Core 10.0 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 11.2% (higher than 96% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)9.1Critical
Exploit odds (30 days)11.2%top 4.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | dotnet10-runtime | 10.0.7-r0 | ALPINE-CVE-2026-40372 |
| Alpine:v3.24 | dotnet10-runtime | 10.0.7-r0 | ALPINE-CVE-2026-40372 |
| NuGet | microsoft.aspnetcore.dataprotection | 10.0.7 | GHSA-9mv3-2cwr-p262 |
| Ubuntu:24.04:LTS | dotnet10 | 10.0.107-10.0.7-0ubuntu1~24.04.1 | UBUNTU-CVE-2026-40372 |
| Ubuntu:25.10 | dotnet10 | 10.0.107-10.0.7-0ubuntu1~25.10.1 | UBUNTU-CVE-2026-40372 |
| Ubuntu:26.04:LTS | dotnet10 | 10.0.107-10.0.7-0ubuntu1~26.04.1 | UBUNTU-CVE-2026-40372 |
| Ubuntu:22.04:LTS | dotnet7 | no fix listed | UBUNTU-CVE-2026-40372 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | ASP.NET Core 10.0 | 10.0 – before 10.0.7 |
| Microsoft | Microsoft Visual Studio 2026 version 18.5 | 18.5.0 – before 18.5.2 |
Weakness: CWE-347 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C
References
- ASP.NET Core Elevation of Privilege Vulnerability vendor-advisory, patch
- https://access.redhat.com/security/cve/CVE-2026-40372 vdb-entry, x_refsource_REDHAT
- RHBZ#2460224 issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-40372.json x_sadp-csaf-vex