CVE-2016-5699

Severity: medium (CVSS 6.1 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 9.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2016-09-02 · updated 2026-06-17
Weakness: CWE-113

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.

Affected products

Python: through 2.7.9; 3.0, 3.0.1, 3.1.0, 3.1.1, 3.1.2, 3.1.3 (+20)

References

http://blog.blindspotsecurity.com/2016/06/advisory-http-header-injection-in.html
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html
http://rhn.redhat.com/errata/RHSA-2016-1626.html
http://rhn.redhat.com/errata/RHSA-2016-1627.html
http://rhn.redhat.com/errata/RHSA-2016-1628.html
http://rhn.redhat.com/errata/RHSA-2016-1629.html
http://rhn.redhat.com/errata/RHSA-2016-1630.html
http://www.openwall.com/lists/oss-security/2016/06/14/7
http://www.openwall.com/lists/oss-security/2016/06/15/12
http://www.openwall.com/lists/oss-security/2016/06/16/2
http://www.oracle.com/technetwork/topics/security/bulletinjul2016-3090568.html
http://www.securityfocus.com/bid/91226

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