Description
CRLF injection vulnerability in the HTTPConnection.putheader function in urllib2 and urllib in CPython (aka Python) before 2.7.10 and 3.x before 3.4.4 allows remote attackers to inject arbitrary HTTP headers via CRLF sequences in a URL.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 11 | python2.7 | 2.7.10~rc1-1 | — |
| Debian 8 | python3.4 | 3.4.2-1+deb8u2 | DLA-1663-1 |
| Debian 7 | python2.7 | 2.7.3-6+deb7u3 | DLA-522-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | python2.7 | 2.7.12-1ubuntu0~16.04.1 | USN-3134-1 |
| Ubuntu 16.04 LTS | python3.5 | 3.5.2-2ubuntu0~16.04.1 | USN-3134-1 |
| Ubuntu 14.04 LTS | python2.7 | 2.7.6-8ubuntu0.3 | USN-3134-1 |
| Ubuntu 14.04 LTS | python3.4 | 3.4.3-1ubuntu1~14.04.5 | USN-3134-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | python +6 | 2.7.5-38.el7_2 | RHSA-2016:1626 |
| RHEL 6 | python +5 | 2.6.6-66.el6_8 | RHSA-2016:1626 |
| RHEL 2 | python27-python +6 | 2.7.8-16.el7 | RHSA-2016:1628 |
| RHEL 2 | python33-python +6 | 3.3.2-16.el7 | RHSA-2016:1629 |
| RHEL 2 | rh-python34-python +6 | 3.4.2-13.el7 | RHSA-2016:1630 |
| RHEL 2 | rh-python35-python +6 | 3.5.1-9.el7 | RHSA-2016:1627 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | python | 2.7.17-7.32.2 | SUSE-SU-2020:0234-1 |
| SLES 15 SP1 | python-base | 2.7.17-7.32.1 | SUSE-SU-2020:0234-1 |
| SLES 15 SP1 | python3 +1 | 3.6.10-3.42.2 | SUSE-SU-2020:0114-1 |
| SLES 15 | python | 2.7.17-7.32.2 | SUSE-SU-2020:0234-1 |
| SLES 15 | python-base | 2.7.17-7.32.1 | SUSE-SU-2020:0234-1 |
| SLES 15 | python3 +1 | 3.6.10-3.42.2 | SUSE-SU-2020:0114-1 |
| SLES 12 SP2 | python3 +1 | 3.4.5-19.1 | SUSE-SU-2016:2859-1 |
| SLES 12 SP1 | python | 2.7.9-24.1 | SUSE-SU-2016:2106-1 |
| SLES 12 SP1 | python-base | 2.7.9-24.2 | SUSE-SU-2016:2106-1 |
| SLES 12 SP1 | python-doc | 2.7.9-24.4 | SUSE-SU-2016:2106-1 |
| SLES 12 SP1 | python3 +1 | 3.4.5-17.1 | SUSE-SU-2016:2653-1 |
| SLES 12 | python | 2.7.9-16.7.1 | SUSE-SU-2019:0223-1 |
| SLES 12 | python-doc +1 | 2.7.9-16.7.2 | SUSE-SU-2019:0223-1 |
| SLES 12 | python3 +1 | 3.4.5-17.1 | SUSE-SU-2016:2653-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 11 SP4 | python +1 | 2.6.9-39.1 | SUSE-SU-2016:2270-1 |
| SLES 11 SP4 | python-doc | 2.6-8.39.1 | SUSE-SU-2016:2270-1 |
| SLES 2 | python | 2.7.17-7.32.2 | SUSE-SU-2020:0234-1 |
| SLES 2 | python-base | 2.7.17-7.32.1 | SUSE-SU-2020:0234-1 |
| SLES for SAP 12 SP2 | python3 +1 | 3.4.5-19.1 | SUSE-SU-2016:2859-1 |
| SLES for SAP 12 SP1 | python | 2.7.9-24.1 | SUSE-SU-2016:2106-1 |
| SLES for SAP 12 SP1 | python-base | 2.7.9-24.2 | SUSE-SU-2016:2106-1 |
| SLES for SAP 12 SP1 | python-doc | 2.7.9-24.4 | SUSE-SU-2016:2106-1 |
| SLES for SAP 12 SP1 | python3 +1 | 3.4.5-17.1 | SUSE-SU-2016:2653-1 |
| SLES for SAP 11 SP4 | python +1 | 2.6.9-39.1 | SUSE-SU-2016:2270-1 |
| SLES for SAP 11 SP4 | python-doc | 2.6-8.39.1 | SUSE-SU-2016:2270-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | python | 2.7.12-1.5 | openSUSE-SU-2024:10450-1 |
| openSUSE Tumbleweed | python-base | 2.7.12-1.4 | openSUSE-SU-2024:10536-1 |
| openSUSE Tumbleweed | python-doc | 2.7.12-1.3 | openSUSE-SU-2024:10193-1 |
| openSUSE Tumbleweed | python36 | 3.6.15-1.1 | openSUSE-SU-2024:11284-1 |
| openSUSE Leap 15.1 | python3 +1 | 3.6.10-lp151.6.7.1 | openSUSE-SU-2020:0086-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | python-py | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | python +6 | 2.7.5-38.0.1.el7_2 | ELSA-2016-1626 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 2 repositories
-
bunseokbot/CVE-2016-5699-poc ★ 4 · Jun 23, 2016
PoC code of CVE-2016-5699 Vulnerability
-
shajinzheng/cve-2016-5699-jinzheng-sha ★ 0 · Aug 23, 2016
Reading Course Report
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 22
- RHSA-2016:1630 Red Hat Security Advisory: rh-python34-python security update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2016:1629 Red Hat Security Advisory: python33-python security update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2016:1627 Red Hat Security Advisory: rh-python35-python security update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2016:1628 Red Hat Security Advisory: python27-python security update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- RHSA-2016:1626 Red Hat Security Advisory: python security update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- USN-3134-1 python2.7, python3.2, python3.4, python3.5 vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DLA-522-1 python2.7 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1663-1 python3.4 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2020:0086-1 Security update for python3 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10450-1 python-2.7.12-1.5 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:2106-1 Security update for python SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:0223-1 Security update for python SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10193-1 python-doc-2.7.12-1.3 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:0114-1 Security update for python3 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:2653-1 Security update for python3 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11284-1 python36-3.6.15-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:2270-1 Security update for python SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:2859-1 Security update for python3 SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10536-1 libpython2_7-1_0-2.7.12-1.4 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:0234-1 Security update for python SUSE / openSUSE Security Updates · May 2, 2025
- WID-SEC-2024-1182 Python: Mehrere Schwachstellen BSI CERT-Bund (WID) · May 20, 2024
- ELSA-2016-1626 Moderate: python security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Aug 18, 2016
References
- http://www.splunk.com/view/SP-CAAAPUE
- https://hg.python.org/cpython/rev/1c45047c5102
- RHSA-2016:1630 vendor-advisory
- RHSA-2016:1627 vendor-advisory
- https://hg.python.org/cpython/rev/bf3e1c9b80e9
- RHSA-2016:1629 vendor-advisory
- http://www.splunk.com/view/SP-CAAAPSV
- [oss-security] 20160616 Re: CVE request: Python HTTP header injection in urrlib2/urllib/httplib/http.client mailing-list
- [debian-lts-announce] 20190207 [SECURITY] [DLA 1663-1] python3.4 security update mailing-list
- http://www.oracle.com/technetwork/topics/security/bulletinjul2016-3090568.html
- https://hg.python.org/cpython/raw-file/v2.7.10/Misc/NEWS
- https://docs.python.org/3.4/whatsnew/changelog.html#python-3-4-4
- [oss-security] 20160615 Re: CVE request: Python HTTP header injection in urrlib2/urllib/httplib/http.client mailing-list
- http://blog.blindspotsecurity.com/2016/06/advisory-http-header-injection-in.html
- [oss-security] 20160614 CVE request: Python HTTP header injection in urrlib2/urllib/httplib/http.client mailing-list
- 91226 vdb-entry
- RHSA-2016:1628 vendor-advisory
- RHSA-2016:1626 vendor-advisory
- openSUSE-SU-2020:0086 vendor-advisory