CVE-2025-55315

CRITICALNVD 9.99.9—Trending — 3 sources updated this weekElevated

9.9

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 v3: 9.9
EG Score: 9.9(medium)
EPSS: 82.5%
KEV: Not listed

Published

October 14, 2025

Last Modified

October 28, 2025

Advisory Details (3)

Auto-updated May 29, 2026

⚠️ Active exploitation confirmed. Patch available. Sources: microsoft.

generic🟡 PoC Available

Kestrel Chunked Smuggling Proof of Concept (CVE-2025-55315) · GitHub

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

generic🔴 Active Exploitation

Understanding the worst .NET vulnerability ever: request smuggling and CVE-2025-55315

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

microsoft Patch Available

Security Update Guide - Microsoft Security Response Center

Security Update Guide - Microsoft Security Response Center. Patch available via Microsoft Security Update

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

Vendor Advisories for CVE-2025-55315(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

RHSA-2025:23225
Red Hat Product SecurityCritical
Red Hat Security Advisory: Red Hat OpenShift Dev Spaces 3.25.0 Release.

Patch Availability(13)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	netstandard-targeting-pack-2.1-8.0 (8.0.121-0ubuntu1~22.04.1) @ jammy	2026-05-29	ubuntu
redhat	dotnet9-0-main-9.0.116-1.hum1	2026-04-21	redhat
redhat	dotnet8-0-main-8.0.126-1.hum1	2026-04-20	redhat
redhat	devspaces/udi-rhel9:3.25.0-1765582207	2025-12-15	redhat
redhat	dotnet10.0-0:10.0.100~rc.2.25502.107-0.10.el9_7	2025-11-11	redhat
redhat	dotnet10.0-0:10.0.100~rc.2.25502.107-0.12.el10_1	2025-11-11	redhat
redhat	dotnet8.0-0:8.0.121-1.el9_4	2025-10-16	redhat
redhat	dotnet9.0-0:9.0.111-1.el8_10	2025-10-15	redhat
redhat	dotnet8.0-0:8.0.121-1.el9_6	2025-10-15	redhat
redhat	dotnet9.0-0:9.0.111-1.el10_0	2025-10-15	redhat
redhat	dotnet8.0-0:8.0.121-1.el8_10	2025-10-15	redhat
redhat	dotnet9.0-0:9.0.111-1.el9_6	2025-10-15	redhat
redhat	dotnet8.0-0:8.0.121-1.el10_0	2025-10-15	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(13 across 1 ecosystem)

NuGet(13)

Package	Vulnerable range	Fixed in	Dependents
Microsoft.AspNetCore.App.Runtime.linux-arm	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.linux-arm64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.linux-musl-arm	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.linux-musl-arm64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.linux-musl-x64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.linux-x64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.osx-arm64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.osx-x64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.win-arm	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.win-arm64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.win-x64	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.App.Runtime.win-x86	10.0.0-rc.1.25451.107	10.0.0-rc.2.25502.107	—
Microsoft.AspNetCore.Server.Kestrel.Core	0.0.1-alpha ... 2.3.0 (22 versions)	2.3.6	—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-444Inconsistent Interpretation of HTTP Requests (HTTP Request Smuggling)

Additional Vendor Advisories

(13)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 11× in last 7d / 11× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-02 20:12 UTCepss_batch
2026-06-02 20:12 UTCepss_batch
2026-06-01 13:51 UTCepss_batch
2026-06-01 13:51 UTCepss_batch
2026-05-31 22:30 UTCepss_batch
2026-05-31 22:30 UTCepss_batch
2026-05-31 00:16 UTCepss_batch
2026-05-31 00:16 UTCepss_batch
2026-05-29 20:53 UTCEG score recompute
2026-05-29 20:53 UTCVendor advisory
2026-05-29 13:44 UTCepss_batch

Publicly available exploits

(3 references)

Working exploit code is in the public domain (2 GitHub PoCs) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

Exploit-DBEDB-52492
First seen Apr 6, 2026
ASP.net 8.0.10 - Bypass
Open source ↗
GitHub PoCZemarKhos/CVE-2025-55315-PoC-Exploit
First seen Nov 11, 2025
CVE-2025-55315 PoC Exploit
Open source ↗
GitHub PoCsirredbeard/CVE-2025-55315-repro
First seen Oct 16, 2025
Tool that reproduces CVE-2025-55315 in ASP.NET Core.
Open source ↗

Frequently asked(5)

What is CVE-2025-55315?

CVE-2025-55315 is a critical vulnerability published on October 14, 2025. 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.

When was CVE-2025-55315 disclosed?

CVE-2025-55315 was first published in the National Vulnerability Database on October 14, 2025, with the most recent update on October 28, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2025-55315 actively exploited?

CVE-2025-55315 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 82.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2025-55315?

CVE-2025-55315 has a CVSS v3 base score of 9.9 (NVD).

How do I remediate CVE-2025-55315?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-55315, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2025-55315

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