high
advisory
Microsoft ASP.NET Core: HTTP Request Smuggling (CVE-2025-55315)
A public proof-of-concept (PoC) exploit has been published for CVE-2025-55315, an HTTP request smuggling vulnerability in Microsoft ASP.NET Core.
CVE search metadata
CVE search record: CVE-2025-55315. Severity: critical. CVSS: 9.9. EPSS: 66.53%. KEV: no. Product: ASP.NET Core, Visual Studio 2022. Brief: Microsoft ASP.NET Core: HTTP Request Smuggling (CVE-2025-55315). Brief link: https://feed.craftedsignal.io/briefs/2026-10-cve-2025-55315-aspnet/
Triage facts
Revision 1- Applicability
- ASP.NET Core, Visual Studio 2022
- Evidence
- Not observed
- Severity
- High
- Sources
- 2 public sources
- Freshness
- Revision 1Oct 29, 00:46 UTC
- Vulnerabilities
- 1 CVE
- Source quality
- B3Likely
CVE-2025-55315 is an HTTP request smuggling vulnerability involving malformed chunked encoding (LF-only line endings) and 'chUnKEd' header bypass. Public proof-of-concept exploitation code has been published. The vulnerability has a CVSS score of 9.9.