Vulnerability record · CVE-2015-5739 · published 18 October 2017
CVE-2015-5739: Golang go http request smuggling vulnerability
Golang · Go
The net/http library in net/textproto/reader.go in Go before 1.4.3 does not properly parse HTTP header keys, which allows remote attackers to conduct HTTP request smuggling attacks via a space instead of a hyphen, as demonstrated by "Content Length" instead of "Content-Length."
Description
The net/http library in net/textproto/reader.go in Go before 1.4.3 does not properly parse HTTP header keys, which allows remote attackers to conduct HTTP request smuggling attacks via a space instead of a hyphen, as demonstrated by "Content Length" instead of "Content-Length."
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
6 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2015-5739), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.