Denial of service in ModSecurity

1) Resource exhaustion

EUVDB-ID: #VU46766

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-15598

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

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

The vulnerability exists due to application does not properly control consumption of internal resources while performing global matching of regular expressions in a combination of the ModSecurity “capture” action. A remote attacker can send a specially crafted HTTP request to the server and perform a denial of service (DoS) attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

ModSecurity: 3.0.0 - 3.0.4

CPE2.3

• cpe:2.3:a:trustwave:modsecurity:3.0.4:*:*:*:*:*:*:*

External links

https://coreruleset.org/20200914/cve-2020-15598/

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.