Vulnerabilities > CVE-2021-32739 - Privilege Defined With Unsafe Actions vulnerability in multiple products

047910
CVSS 6.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL
network
low complexity
icinga
debian
CWE-267

Summary

Icinga is a monitoring system which checks the availability of network resources, notifies users of outages, and generates performance data for reporting. From version 2.4.0 through version 2.12.4, a vulnerability exists that may allow privilege escalation for authenticated API users. With a read-ony user's credentials, an attacker can view most attributes of all config objects including `ticket_salt` of `ApiListener`. This salt is enough to compute a ticket for every possible common name (CN). A ticket, the master node's certificate, and a self-signed certificate are enough to successfully request the desired certificate from Icinga. That certificate may in turn be used to steal an endpoint or API user's identity. Versions 2.12.5 and 2.11.10 both contain a fix the vulnerability. As a workaround, one may either specify queryable types explicitly or filter out ApiListener objects.

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Restful Privilege Elevation
    Rest uses standard HTTP (Get, Put, Delete) style permissions methods, but these are not necessarily correlated generally with back end programs. Strict interpretation of HTTP get methods means that these HTTP Get services should not be used to delete information on the server, but there is no access control mechanism to back up this logic. This means that unless the services are properly ACL'd and the application's service implementation are following these guidelines then an HTTP request can easily execute a delete or update on the server side. The attacker identifies a HTTP Get URL such as http://victimsite/updateOrder, which calls out to a program to update orders on a database or other resource. The URL is not idempotent so the request can be submitted multiple times by the attacker, additionally, the attacker may be able to exploit the URL published as a Get method that actually performs updates (instead of merely retrieving data). This may result in malicious or inadvertent altering of data on the server.