#VU52847 Security features bypass in Redmine - CVE-2021-31865

Vulnerability identifier: #VU52847

Vulnerability risk: Medium

CVSSv4.0: 2.7 [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:U/U:Green]

CVE-ID: CVE-2021-31865

CWE-ID: CWE-254

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Redmine
Web applications / CRM systems

Vendor: Ruby

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the security features bypass issue. A remote attacker can send a specially crafted request and circumvent the allowed filename extensions of uploaded attachments.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Redmine: 4.0.0 - 4.2.0

---

External links
https://www.redmine.org/projects/redmine/wiki/Security_Advisories
https://www.redmine.org/news/131

---

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.