Denial of service in Cloud Foundry cflinuxfs3

Published: 2021-03-25 | Updated: 2021-04-06
Risk Medium
Patch available YES
Number of vulnerabilities 1
CVE ID CVE-2021-3449
Exploitation vector Network
Public exploit Public exploit code for vulnerability #1 is available.
Vulnerable software
Other software / Other software solutions

Vendor Cloud Foundry Foundation

Security Advisory

This security advisory describes one medium risk vulnerability.

1) NULL pointer dereference

Risk: Medium

CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C] [PCI]

CVE-ID: CVE-2021-3449

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: Yes


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error when processing TLSv1.2 renegotiations. A remote attacker can send a maliciously crafted renegotiation ClientHello message, which omits the signature_algorithms extension but includes a signature_algorithms_cert extension, trigger a NULL pointer dereference error and crash the server.


Install update from vendor's website.

Vulnerable software versions

cflinuxfs3: 0.200.0, 0.201.0, 0.202.0, 0.203.0, 0.204.0, 0.205.0, 0.206.0, 0.207.0, 0.208.0, 0.209.0, 0.210.0, 0.211.0, 0.212.0, 0.213.0, 0.214.0, 0.215.0, 0.216.0, 0.217.0, 0.218.0, 0.219.0, 0.220.0, 0.221.0, 0.222.0, 0.223.0, 0.224.0, 0.225.0, 0.226.0, 0.227.0, 0.228.0, 0.229.0, 0.230.0, 0.231.0, 0.233.0, 0.234.0

CPE External links

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.