CRLF Injection Vulnerability in urllib3 Affecting Python
CVE-2020-26137

6.5MEDIUM

Key Information:

Vendor

Python

Status
Urllib3
Vendor
CVE Published:
30 September 2020

What is CVE-2020-26137?

The vulnerability in urllib3 affects versions prior to 1.25.9, allowing attackers to exploit the handling of HTTP request methods. By inserting Carriage Return (CR) and Line Feed (LF) control characters into the initial argument of putrequest(), malicious users can manipulate HTTP requests, potentially leading to significant security breaches. The flaw is reminiscent of previous vulnerabilities, highlighting the importance of keeping libraries updated to safeguard web applications against request-based attacks.

References

https://bugs.python.org/issue39603
https://github.com/urllib3/urllib3/pull/1800
https://github.com/urllib3/urllib3/commit/1dd69c5c5982fae...

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.