Vulnerability identifier: #VU53004

Vulnerability risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-22904

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Ruby on Rails
Universal components / Libraries / Scripting languages

Vendor: Rails

Description

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

The vulnerability exists due to a use-after-free error in the Token Authentication logic in Action Controller. A remote attacker can send a specially crafted request and cause a denial of service condition on the target system. 

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Ruby on Rails: 4.2.0 - 4.2.11.3, 4.1.0 - 4.1.16 rc1, 4.0.0 - 4.0.13 rc1, 5.2.0 - 5.2.5, 5.1.0 - 5.1.7, 5.0.0 - 5.0.7.2, 6.1.0 - 6.1.3.1, 6.0.0 - 6.0.3.6

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External links
http://seclists.org/oss-sec/2021/q2/102

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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.