ASP.NET Core
CVE-2025-55315 — ASP.NET Security Feature Bypass Vulnerability
Executive Summary
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.
Overview
9.9
CVSS CRITICAL
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
CVSS Vector
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
ATTACK VECTOR
Network
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
Low
USER INTERACTION
None
SCOPE
Changed
CONFIDENTIALITY
High
INTEGRITY
High
AVAILABILITY
Low
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 8.6
EPSS Score
0.65838
probability of exploitation in the next 30 days
0.99204 percentile - updated 2026-08-14
View on FIRST.org
Affected Products
6 affected products
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| ASP.NET Core 2.3 | Release Notes (Security Update) |
Important | Security Feature Bypass | Maybe |
| ASP.NET Core 8.0 | 5068331 (Security Update) |
Important | Security Feature Bypass | Maybe |
| ASP.NET Core 9.0 | 5068332 (Security Update) |
Important | Security Feature Bypass | Maybe |
| Microsoft Visual Studio 2022 version 17.10 | Release Notes (Security Update) |
Important | Security Feature Bypass | Maybe |
| Microsoft Visual Studio 2022 version 17.12 | Release Notes (Security Update) |
Important | Security Feature Bypass | Maybe |
| Microsoft Visual Studio 2022 version 17.14 | Release Notes (Security Update) |
Important | Security Feature Bypass | Maybe |
Patches
3 patches
| Article | Type | Restart |
|---|---|---|
Release Notes |
Security Update | Maybe |
5068331 |
Security Update | Maybe |
5068332 |
Security Update | Maybe |
Exploits & PoC
7 public PoCsUnverified third-party code
Public proof-of-concept repositories aggregated from PoC-in-GitHub. They are not reviewed and may be incomplete, non-functional, or malicious — inspect the code before running anything.
| Repository | Stars | Published | Description |
|---|---|---|---|
| sirredbeard/CVE-2025-55315-repro | 46 | 2025-10-16 | Tool that reproduces CVE-2025-55315 in ASP.NET Core. |
| ZemarKhos/CVE-2025-55315-PoC-Exploit | 9 | 2025-11-11 | CVE-2025-55315 PoC Exploit |
| nickcopi/CVE-2025-55315-detection-playground | 7 | 2025-10-16 | Playground to experiment with different behavior on patched/unpatched Kestrel for the CVE-2025-55315 HTTP smuggling vulnerability |
| 7huukdlnkjkjba/CVE-2025-55315- | 6 | 2025-10-19 | 专业级HTTP请求走私漏洞利用与自动化渗透测试工具 |
| jlinebau/CVE-2025-55315-Scanner-Monitor | 2 | 2025-10-24 | Quick and Simple Scripts to Scan for Vulnerable Servers and Packet Level Monitors |
| MartinFabianIonut/CVE-2025-55315 | 1 | 2025-11-27 | Proof-of-concept exploit for CVE-2025-55315 (.NET HTTP Request Smuggling). Demonstrates how improperly parsed chunked encoding lets attackers smuggle requests past proxies and load balancers in vulner |
| NetVanguard-cmd/CVE-2025-55315 | 0 | 2026-04-19 |
Detection Rules
No public Sigma or Nuclei detection rule has been mapped to this CVE yet. Coverage is concentrated on exploited / high-profile vulnerabilities; check SigmaHQ for updates.
Acknowledgments
Sid
References
On This Page