CVE-2018-20852

Description

http.cookiejar.DefaultPolicy.domain_return_ok in Lib/http/cookiejar.py in Python before 3.7.3 does not correctly validate the domain: it can be tricked into sending existing cookies to the wrong server. An attacker may abuse this flaw by using a server with a hostname that has another valid hostname as a suffix (e.g., pythonicexample.com to steal cookies for example.com). When a program uses http.cookiejar.DefaultPolicy and tries to do an HTTP connection to an attacker-controlled server, existing cookies can be leaked to the attacker. This affects 2.x through 2.7.16, 3.x before 3.4.10, 3.5.x before 3.5.7, 3.6.x before 3.6.9, and 3.7.x before 3.7.3.

References

https://www.oracle.com/security-alerts/cpuapr2020.html

https://usn.ubuntu.com/4127-2/

https://usn.ubuntu.com/4127-1/

https://security.gentoo.org/glsa/202003-26

https://python-security.readthedocs.io/vuln/cookie-domain-check.html

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZBTGPBUABGXZ7WH7677OEM3NSP6ZEA76/

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K7HNVIFMETMFWWWUNTB72KYJYXCZOS5V/

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/COATURTCY7G67AYI6UDV5B2JZTBCKIDX/

https://lists.debian.org/debian-lts-announce/2020/08/msg00034.html

https://lists.debian.org/debian-lts-announce/2020/07/msg00011.html

https://lists.debian.org/debian-lts-announce/2019/08/msg00040.html

https://lists.debian.org/debian-lts-announce/2019/08/msg00022.html

https://bugs.python.org/issue35121

https://access.redhat.com/errata/RHSA-2019:3948

https://access.redhat.com/errata/RHSA-2019:3725

http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html

http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00074.html

http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00071.html

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3