VulnerabilityModified

CVE-2025-55315

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.

CRITICAL 9.9EPSS 65.8%

Does this matter?

EPSS puts the probability of exploitation in the next 30 days at 65.8%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.

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: 9.9 CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
EPSS: 65.84% probability · 99th percentile
CISA KEV: Not listed
Weakness: CWE-444
Affected: microsoft/asp.net core · microsoft/visual studio 2022
Source: secure@microsoft.com

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-55315Vendor Advisory
https://andrewlock.net/understanding-the-worst-dotnet-vulnerability-request-smuggling-and-cve-2025-55315/
https://gist.github.com/N3mes1s/d0897c13ca199e739ecc2b562f466040

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.