September 6, 2023 CISA KEV Breakdown | Apache

September 6: 1 New Vuln | CVE-2023-33246

In this CISA KEV Breakdown, a reawakened botnet campaign targets the use of Apache’s RocketMQ in activity spotted by Juniper Networks in early June of this year.

[wptb id=22505]

Notable Vulnerability Additions

CVE-2023-33246 | RocketMQ Remote Code Execution

A vulnerability exists in Apache RocketMQ 5.1.0 and below and 4.9.5 and below which can allow a remote attacker to execute arbitrary code on the vulnerable host running the RocketMQ application. An attacker would need to send a malicious request with a predefined code value that reaches the UPDATE_BROKER_CONFIG function which proceeds to update the broker.conf file on the vulnerable host. This opened the door for attackers to implant shells on the host system due to the lack of authorization around the calling of the function.

Alongside a report on recent DreamBus botnet campaign activity, Juniper Networks also released an explainer blog back in June on the exploitation of this vulnerability. The ultimate motivation of the botnet campaign resurfacing according to their analysis is, you guessed it, monetary gain. Initial activity surrounding the use of the vulnerability pointed to the fact that attackers were pointing the boxes to interactsh through the oast.pro domain. This would be a good time to point out that if you do not have detection around activity which points to one of the following *.oast.* domains, it may be worth it if you know your organization does not use interactsh:

• oast.pro
• oast.live
• oast.site
• oast.online
• oast.fun
• oast.me

The motivation for the attackers to initially utilize interactsh isn’t exactly clear aside from the gaining of useful recon data. It didn’t take long for attackers utilizing the exploit to drop DreamBus which leapt to attempted cryptominer installations. A fix for the vulnerability was released in May of this year, with fixes to both 5.1.1 and 4.9.6.

Security Advisory(s):

https://lists.apache.org/thread/1s8j2c8kogthtpv3060yddk03zq0pxyp

← August 24, 2023 CISA Kev Breakdown

Click here to expand our CISA KEV Breakdown Frequently Asked Questions

• What makes for a notable addition?
  • A notable addition can arise from many different characteristics. If a particular vulnerability is notable to the security community or a subset of the security community or if the EPSS score reveals notable information about the vulnerability, this can constitute further analysis. It may also be the case that a particular vulnerability shines a light on everyday users and we will highlight important information and key takeaways to ensure users and readers have easy access to actionable information.
• When is the Breakdown released?
  • We aim to have our analysis of each KEV update posted within 24 hours of the time in which the Catalog is updated. See CISA’s full catalog here
• I am not bound by BOD 22-01 or federal regulations, why should the KEV concern me?
  • CISA encourages all organizations to utilize the Catalog as an attribute in your vulnerability prioritization framework. Organizations looking to lessen the scope on known dangerous vulnerabilities and make a goal to remediate them can understand where they currently stand against what CISA has confirmed as exploited vulnerabilities in the wild. See CISA’s section on “How should organizations use the KEV catalog?” here.
• What is EPSS?
  • EPSS is the Exploit Prediction Scoring System. It is an open, data-driven effort for estimating the likelihood (probability) that a software vulnerability will be exploited in the wild. See the EPSS home page on FIRST for more information here.
• What is the difference between EPSS probability and EPSS percent?
  • EPSS probability is the risk calculated by the model when determining the perceived threat of the vulnerability itself. Percentage is a relative comparison of the rest of the CVEs within the given sample. While the probability only changes upon refreshing the results from the model, the percentage can change purely based on the CVE sample given. In the case of the Breakdown, we use the percentage given by the pool of all CVEs with given EPSS data. Scores may vary post-release of the post given new information about the vulnerabilities and their perceived threat. For more information on applying and understanding EPSS data, see this article on the FIRST website, as well as their FAQ page.
• What is GreyNoise?
  • GreyNoise is a platform that collects, analyzes, and labels data on IPs that scan the internet and saturate security tools with noise. Through their sensor network, GreyNoise observes vulnerability exploitation attempts for vulnerabilities that are exploited in the wild over the Internet. These are arguably vulnerabilities that should be at the very top of your priority list to remediate.
• Why are GreyNoise exploitation attempts only observed on ~20% of KEV vulnerabilities?
  • Exploitation of many vulnerabilities in the CISA KEV will not be observed for many reasons that GreyNoise does a good job of explaining in this post. For example:
    • The vulnerability may not be remotely exploitable
    • Vulnerability exploitation may require authentication (and result in privilege escalation)
    • The impacted software may not be exposed to the internet
    • Mass scanning/exploitation is not occurring yet