CVE-2025-55315criticalCWE-444

CVE-2025-55315: critical vulnerability in Microsoft ASP.NET Core 2.3

ASP.NET Security Feature Bypass Vulnerability

Published · Updated

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62Vexday Risk Score

Keep watching. It has a public proof of concept.

ssvc Attendcvss 9.9epss 67%
from disclosure to weapon2 days
Published on NVDOct 14
1st PoC+2d
What the vendors declare (VEX)

Official vendor statements in CSAF/VEX format: whether their product is affected, already fixed, or ruled out — and why. These are the vendor's assertions, not Vexday's judgment.

Red HatVEX document ↗
Affected
1 product (22 components)
Red Hat Enterprise Linux 9
workaround: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Fixed
10 products (977 components)
Red Hat Enterprise Linux AppStream (v. 9) · Red Hat Enterprise Linux AppStream (v. 10) · Red Hat Enterprise Linux AppStream (v. 8) · Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · and others 5
fix ↗
Not affected
2 products (62 components) — because the vulnerable code is not present in the product
Red Hat OpenShift Dev Spaces (RHOSDS) 3.25 · Red Hat Hardened Images
In short

ASP.NET Core has a flaw that lets an authorized attacker send specially crafted HTTP requests to trick the server into processing malicious data that should have been blocked, bypassing built-in security protections.

Technical detail

HTTP request smuggling vulnerability in ASP.NET Core due to inconsistent interpretation of HTTP requests between the application and intermediate components. An authorized attacker can exploit this to bypass security features; the attack requires network access but no elevated privileges beyond basic authorization.

Summary generated and translated by AI from the official 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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L/E:U/RL:O/RC:C
Affected products
Microsoft · ASP.NET Core 2.3Microsoft · ASP.NET Core 8.0Microsoft · ASP.NET Core 9.0Microsoft · Microsoft Visual Studio 2022 version 17.10Microsoft · Microsoft Visual Studio 2022 version 17.12Microsoft · Microsoft Visual Studio 2022 version 17.14
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — Microsoft ASP.NET Core 2.3

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