Vulnerability in Python

CVE-2016-5699

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.

EPSS: 0.102 (95.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

  • Python — versions 3.0, 3.0.1, 3.1.0
  • N/a — versions n/a

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2016-5699?
CVE-2016-5699 is a medium-severity vulnerability in Python, classified under HTTP Response Splitting. CVSS score: 6.1/10. Published 2016-09-02.
How severe is CVE-2016-5699?
Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2016-5699 known to be exploited?
7 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.