CVE-2026-102870
Description
Improper control of generation of code ('code injection') in ASP.NET Core allows an unauthorized attacker to execute code over a network.
Statement
A code injection vulnerability was found in the Blazor WebAssembly debug proxy of ASP.NET Core, which is shipped in the dotnet10.0 packages in Red Hat Enterprise Linux 8, 9, and 10, Red Hat In-Vehicle OS, and Fedora. The debug proxy embeds attacker-controlled values, such as ToString() results, descriptions, and class names, into generated C# code without consistently escaping them. When a developer evaluates an expression while debugging a Blazor WebAssembly application, a malicious value can escape the generated string literal and execute arbitrary code on the developer's machine. Red Hat rated this flaw as IMPORTANT (CVSS 3.1 score of 8.8, CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), matching the upstream Microsoft severity; exploitation requires no privileges but relies on a developer interacting with attacker-controlled values during a debugging session. The .NET 8 based dotnet8.0 builds in Red Hat Hardened Images were determined to be not affected because the vulnerable component is not present there. This flaw is tracked as DELEGATED, and a fix for the affected Red Hat products is being pursued.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.8 | N/A | 8.8 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Red Hat CVSS v3 Score Explanation
Microsoft CNA CVSS from pre-release advisory
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