CVE-2025-22871: Request smuggling due to acceptance of invalid chunked data in net/http

Description

The net/http package improperly accepts a bare LF as a line terminator in chunked data chunk-size lines. This can permit request smuggling if a net/http server is used in conjunction with a server that incorrectly accepts a bare LF as part of a chunk-ext.

Classification

CVE ID: CVE-2025-22871

Problem Types

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

Affected Products

Vendor: Go standard library

Product: net/http/internal

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.01% (probability of being exploited)

EPSS Percentile: 0.42% (scored less or equal to compared to others)

EPSS Date: 2025-04-18 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-22871
https://go.dev/cl/652998
https://go.dev/issue/71988
https://groups.google.com/g/golang-announce/c/Y2uBTVKjBQk
https://pkg.go.dev/vuln/GO-2025-3563

Timeline