Log4Shell Still Being Exploited to Hack VMWare Servers to Exfiltrate Sensitive Data
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2021-44228 | JNDI Injection Remote Code Execution in Apache Log4j2 (Log4Shell) Apache Log4j2, an extremely widely used Java logging library, fails to protect its JNDI lookup feature against attacker-controlled JNDI-related endpoints (CWE-20, CWE-502), so crafted text processed by the logger causes the Java runtime to fetch and load attacker-supplied objects, leading to remote code execution. The flaw is triggered whenever attacker-controlled input reaches the logging API and is parsed for JNDI lookups, a pattern common in web servers and enterprise Java applications that log user-supplied fields such as headers or form values. Successful exploitation yields arbitrary code execution under the privileges of the affected application, giving attackers a foothold for lateral movement, data theft, and ransomware deployment. Any Java application or product that ships or bundles an affected Apache Log4j2 release is exposed, making this one of the most broadly deployed vulnerabilities ever disclosed. Exploitation is confirmed in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2021-12-10 with known ransomware use, and EPSS assigns a 100% probability of exploitation within 30 days. Do: Inventory all Java applications and dependencies for Apache Log4j2 and apply the vendor's patched updates, or remove affected assets from the network, as required by CISA's KEV catalog. Where updates are not yet available, use the temporary mitigations in CISA's ED-22-02 recommended-mitigation guidance, such as disabling message lookups, only until patches are applied. Prioritize internet-facing and business-critical systems and hunt for exploitation activity given known ransomware use. | 10.0 | 100% | KEV ransomware PoC ×9 |
| masshundreds of millions of Java applications/devices, with hundreds of thousands of internet-exposed services | |
| CVE-2022-22954 | Server-Side Template Injection RCE in VMware Workspace ONE Access and Identity Manager CVE-2022-22954 is a server-side template injection vulnerability (CWE-94) in VMware Workspace ONE Access and VMware Identity Manager that allows remote code execution on affected appliances. It is triggered when attacker-controlled input is passed into a server-side template engine, allowing injected template directives to be evaluated and executed as code on the server. A successful attacker gains the ability to run arbitrary code on the identity appliance, and CISA notes the flaw has been used in ransomware campaigns, so compromise can serve as an initial foothold for broader enterprise intrusion. Any organization running Workspace ONE Access or Identity Manager, including deployments where the Identity Manager component is bundled into VMware Horizon environments, is potentially affected, though the source data does not specify affected version ranges. The vulnerability was added to CISA's Known Exploited Vulnerabilities catalog on 2022-04-14 with ransomware use confirmed and a required action to apply vendor updates, and EPSS currently assigns it a 100% probability of exploitation within 30 days (100th percentile); no public PoC is known. Do: Apply the patches published in VMware advisory VMSA-2022-0011 (April 2022) to Workspace ONE Access and Identity Manager appliances as required by the CISA KEV listing, prioritizing internet-facing instances, and restrict or remove public exposure until patched. Review appliance and web-server logs for template-injection probes and unexpected processes spawned by the identity service, and investigate any indications of compromise for follow-on ransomware or lateral-movement activity. | 9.8 | 100% | KEV ransomware PoC |
| large≈ tens of thousands of internet-exposed Workspace ONE Access / Identity Manager instances (order-of-magnitude estimate; exact count unknown) |
Full article513 words · extracted from thehackernews.com · click to collapse
Ravie LakshmananJun 24, 2022
The U.S. Cybersecurity and Infrastructure Security Agency (CISA), along with the Coast Guard Cyber Command (CGCYBER), on Thursday released a joint advisory warning of continued attempts on the part of threat actors to exploit the Log4Shell flaw in VMware Horizon servers to breach target networks.
"Since December 2021, multiple threat actor groups have exploited Log4Shell on unpatched, public-facing VMware Horizon and [Unified Access Gateway] servers," the agencies said. "As part of this exploitation, suspected APT actors implanted loader malware on compromised systems with embedded executables enabling remote command-and-control (C2)."
In one instance, the adversary is said to have been able to move laterally inside the victim network, obtain access to a disaster recovery network, and collect and exfiltrate sensitive law enforcement data.
Log4Shell, tracked as CVE-2021-44228 (CVSS score: 10.0), is a remote code execution vulnerability affecting the Apache Log4j logging library that's used by a wide range of consumers and enterprise services, websites, applications, and other products.
Successful exploitation of the flaw could enable an attacker to send a specially-crafted command to an affected system, enabling the actors to execute malicious code and seize control of the target.
Based on information gathered as part of two incident response engagements, the agencies said that the attackers weaponized the exploit to drop rogue payloads, including PowerShell scripts and a remote access tool dubbed "hmsvc.exe" that's equipped with capabilities to log keystrokes and deploy additional malware.
"The malware can function as a C2 tunneling proxy, allowing a remote operator to pivot to other systems and move further into a network," the agencies noted, adding it also offers a "graphical user interface (GUI) access over a target Windows system's desktop."
The PowerShell scripts, observed in the production environment of a second organization, facilitated lateral movement, enabling the APT actors to implant loader malware containing executables that include the ability to remotely monitor a system's desktop, gain reverse shell access, exfiltrate data, and upload and execute next-stage binaries.
Furthermore, the adversarial collective leveraged CVE-2022-22954, a remote code execution vulnerability in VMware Workspace ONE Access and Identity Manager that came to light in April 2022, to deliver the Dingo J-spy web shell.
Ongoing Log4Shell-related activity even after more than six months suggests that the flaw is of high interest to attackers, including state-sponsored advanced persistent threat (APT) actors, who have opportunistically targeted unpatched servers to gain an initial foothold for follow-on activity.
According to cybersecurity company ExtraHop, Log4j vulnerabilities have been subjected to relentless scanning attempts, with financial and healthcare sectors emerging as an outsized market for potential attacks.
"Log4j is here to stay, we will see attackers leveraging it again and again," IBM-owned Randori said in an April 2022 report. "Log4j buried deep into layers and layers of shared third-party code, leading us to the conclusion that we'll see instances of the Log4j vulnerability being exploited in services used by organizations that use a lot of open source."
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2022/06/log4shell-still-being-exploited-to-hack.html