Improper input validation in Python
CVE-2018-20852
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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.040 (89.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
Affected products
- Python
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (Exploit, x_refsource_MISC, Issue Tracking, Vendor Advisory)
- cve@mitre.org (x_refsource_MISC, Vendor Advisory)
- cve@mitre.org (mailing-list, x_refsource_MLIST)
- cve@mitre.org (vendor-advisory, x_refsource_SUSE)
- cve@mitre.org (vendor-advisory, x_refsource_SUSE)
- cve@mitre.org (mailing-list, x_refsource_MLIST)
- cve@mitre.org (x_refsource_UBUNTU, vendor-advisory)
- cve@mitre.org (x_refsource_UBUNTU, vendor-advisory)
- cve@mitre.org (x_refsource_REDHAT, vendor-advisory)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
Frequently asked questions
- What is CVE-2018-20852?
- CVE-2018-20852 is a medium-severity vulnerability in Python, classified under Improper Input Validation. CVSS score: 5.3/10. Published 2019-07-13.
- How severe is CVE-2018-20852?
- Medium severity. CVSS v3 base score is 5.3 out of 10.
- Is CVE-2018-20852 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.