CVE-2020-26116

high

Description

http.client in Python 3.x before 3.5.10, 3.6.x before 3.6.12, 3.7.x before 3.7.9, and 3.8.x before 3.8.5 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of HTTPConnection.request.

References

Advisories
More

https://www.oracle.com/security-alerts/cpuoct2021.html

https://usn.ubuntu.com/4581-1/

https://security.netapp.com/advisory/ntap-20201023-0001/

https://security.gentoo.org/glsa/202101-18

https://python-security.readthedocs.io/vuln/http-header-injection-method.html

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QOX7DGMMWWL6POCRYGAUCISOLR2IG3XV/

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OXI72HIHMXCQFWTULUXDG7VDA2BCYL4Y/

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JWMAVY4T4257AZHTF2RZJKNJNSJFY24O/

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HDQ2THWU4GPV4Y5H5WW5PFMSWXL2CRFD/

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BW4GCLQISJCOEGQNIMVUZDQMIY6RR6CC/

https://lists.debian.org/debian-lts-announce/2020/11/msg00032.html

http://lists.opensuse.org/opensuse-security-announce/2020-11/msg00027.html

https://github.com/advisories/GHSA-wqvq-5m8c-6g24

https://github.com/opencve/opencve

https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html

https://bugs.python.org/issue39603

Details

Source: Mitre, NVD

Published: 2020-09-27

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 7.2

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Severity: High

EPSS

EPSS: 0.0034