CVE-2025-55315

Published: Oct 14, 2025Modified: Oct 18, 2026

9.9

Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L

Exploitability: 3.1 / Impact: 6.0

Source: secure@microsoft.com (Secondary)

Description

Inconsistent interpretation of http requests ('http request/response smuggling') in ASP.NET Core allows an authorized attacker to bypass a security feature over a network.

Affected (6)

Products: Microsoft: Asp.net Core, Visual Studio 2022

Microsoft

2 products

Asp.net Core

Visual Studio 2022

Configuration A

6 vulnerable

Vulnerable Software	Affected Versions
Microsoft Asp.net Core	2.3.0 ≤ version < 2.3.6
Microsoft Asp.net Core	8.0.0 ≤ version < 8.0.21
Microsoft Asp.net Core	9.0.0 ≤ version < 9.0.10
Microsoft Visual Studio 2022	17.10.0 ≤ version < 17.10.20
Microsoft Visual Studio 2022	17.12.10 ≤ version < 17.12.13
Microsoft Visual Studio 2022	17.14.0 ≤ version < 17.14.17

Related CWEs

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

References (3)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-55315

Source: secure@microsoft.com

Vendor Advisory

https://andrewlock.net/understanding-the-worst-dotnet-vulnerability-request-smuggling-and-cve-2025-55315/

Source: af854a3a-2127-422b-91ae-364da2661108

https://gist.github.com/N3mes1s/d0897c13ca199e739ecc2b562f466040

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

Timeline

No history available yet.