CVE-2025-55315 | BDVDB-2026-297944 Detail

MicrosoftASP.NET Core 2.3

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.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact low. Attack vector: network.

Weaknesses#

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

References#

Exploit#

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

History#

Version 12025-10-14Record published in the CVE List.
Version 22026-02-22Most recent update recorded in the CVE List.

Published

Published: 2025-10-14
Last modified: 2026-02-22

Vendor information

Vendor: Microsoft
Product: ASP.NET Core 2.3

All Microsoft vulnerabilities

Score

9.9 Critical

EPSS

67.1%, High

Estimated chance of exploitation in the next 30 days. EPSS percentile: 99.3.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
>= 2.3 and < 2.3.6
Fixed
2.3.6

Scoring System

CVSS v4.0

Not available

CVSS v3.1

9.9 Critical

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

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	Low
User Interaction	None
Scope	Changed
Confidentiality	High
Integrity	High
Availability	Low

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).