2021-27293 | RestSharp incorrect regex

By Max On Jul 15, 2021

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4.1	$0-$5k	0.38

A vulnerability was found in RestSharp. It has been rated as critical. Affected by this issue is an unknown function. The manipulation of the argument DateTimes with an unknown input leads to a privilege escalation vulnerability. Using CWE to declare the problem leads to CWE-185. Impacted is availability. CVE summarizes:

RestSharp < 106.11.8-alpha.0.13 uses a regular expression which is vulnerable to Regular Expression Denial of Service (ReDoS) when converting strings into DateTimes. If a server responds with a malicious string, the client using RestSharp will be stuck processing it for an exceedingly long time. Thus the remote server can trigger Denial of Service.

The weakness was disclosed 07/12/2021. The advisory is available at github.com. This vulnerability is handled as CVE-2021-27293 since 02/16/2021. The attack may be launched remotely. The successful exploitation requires a simple authentication. Technical details are known, but there is no available exploit.

Upgrading to version 106.11.8-alpha.0.13 eliminates this vulnerability.

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