CVE-2015-5740

The net/http library in net/http/transfer.go in Go before 1.4.3 does not properly parse HTTP...

9.8 CriticalFix available

The net/http library in net/http/transfer.go in Go before 1.4.3 does not properly parse HTTP headers, which allows remote attackers to conduct HTTP request smuggling attacks via a request with two Content-length headers.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: High

Exploit likelihood

3.66%Up 2.2 points since Feb 4, 2022

What each source reports

NVD Score used 9.8

Record: CVE-2015-5740
CVSS 3.0: 9.8 CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0: 7.5 HighAV:N/AC:L/Au:N/C:P/I:P/A:P
Weakness: CWE-444
Updated: 2026-11-02

CVE List No score

Record: CVE-2015-5740
Updated: 2026-11-02

EUVDEUVD-2015-5686 No score

Record: EUVD-2015-5686
Updated: 2026-11-03

GitHub AdvisoriesGHSA-8vhq-594p-r648 9.8

The net/http library in net/http/transfer.go in Go before 1.4.3 does not properly parse HTTP...

Record: GHSA-8vhq-594p-r648
CVSS 3.0: 9.8 CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness: CWE-444
Updated: 2026-11-02

OSVRHSA-2016:1538 5.3

Red Hat Security Advisory: golang security, bug fix, and enhancement update

Record: RHSA-2016:1538
CVSS 3.0: 5.3 MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Updated: 2026-11-02

OSVUBUNTU-CVE-2015-5740 9.8

Record: UBUNTU-CVE-2015-5740
CVSS 3.0: 9.8 CriticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated: 2026-11-02

OSVGO-2021-0159 No score

Request smuggling due to improper header parsing in net/http

HTTP headers were not properly parsed, which allows remote attackers to conduct HTTP request smuggling attacks via a request that contains Content-Length and Transfer-Encoding header fields.

Record: GO-2021-0159
Updated: 2026-11-02

Affected products

Affected packages

Affected packages
Package	Affected	Fixed
`stdlib` Go	before 1.4.3	1.4.3
`golang` Red Hat:enterprise_linux:7::server	before 0:1.6.3-1.el7_2.1	0:1.6.3-1.el7_2.1
`golang-bin` Red Hat:enterprise_linux:7::server	before 0:1.6.3-1.el7_2.1	0:1.6.3-1.el7_2.1
`golang-docs` Red Hat:enterprise_linux:7::server	before 0:1.6.3-1.el7_2.1	0:1.6.3-1.el7_2.1
`golang-misc` Red Hat:enterprise_linux:7::server	before 0:1.6.3-1.el7_2.1	0:1.6.3-1.el7_2.1
`golang-src` Red Hat:enterprise_linux:7::server	before 0:1.6.3-1.el7_2.1	0:1.6.3-1.el7_2.1
`golang-tests` Red Hat:enterprise_linux:7::server	before 0:1.6.3-1.el7_2.1	0:1.6.3-1.el7_2.1
`gccgo-4.9` Ubuntu:14.04:LTS	All versions, plus listed versions 4.9-20140213-0ubuntu14.9-20140213-0ubuntu24.9-20140217-0ubuntu14.9-20140222-0ubuntu14.9-20140303-0ubuntu2 Show 6 moreShow less 4.9-20140303-0ubuntu34.9-20140321-0ubuntu14.9-20140330-0ubuntu14.9-20140406-0ubuntu14.9.1-0ubuntu14.9.3-0ubuntu4	None known

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2015-5740 is a critical vulnerability (CVSS 9.8) in Golang Go, published October 18, 2017. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.66%, the 89th percentile. Fixed in stdlib 1.4.3.

References

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