#VU26412 CRLF injection in urllib3 - CVE-2019-11236

Vulnerability identifier: #VU26412

Vulnerability risk: Medium

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2019-11236

CWE-ID: CWE-93

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
urllib3
Web applications / Modules and components for CMS

Vendor: urlib3

Description

The vulnerability allows a remote attacker to perform a spoofing attack.

The vulnerability exists due to insufficient filtration of user-supplied data passed via HTTP request parameters to urllib3 library. A remote attacker can pass specially crafted data that contains CRLF sequences and perform a spoofing attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

urllib3: 1.24 - 1.24.2

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External links
https://github.com/urllib3/urllib3/issues/1553
https://lists.debian.org/debian-lts-announce/2019/06/msg00016.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/R62XGEYPUTXMRHGX5I37EBCGQ5COHGKR/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TBI45HO533KYHNB5YRO43TBYKA3E3VRL/
https://usn.ubuntu.com/3990-1/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.