Russian Hackers Exploit New NTLM Flaw to Deploy RAT Malware via Phishing Emails
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2024-43451 | NTLMv2 Hash Disclosure Spoofing Vulnerability in Microsoft Windows CVE-2024-43451 is a flaw in the NTLM authentication implementation of Microsoft Windows that lets an attacker obtain a user's NTLMv2 authentication hash. It requires user interaction: a victim who engages with attacker-supplied content, such as a crafted file or an attacker-controlled file path/URL reference (consistent with the CWE-73 external control of file name weakness), causes Windows to silently initiate an NTLM authentication to a hostile host, leaking the hash. An attacker who captures the hash can crack it offline to recover the user's password or relay it to authenticate (spoof) as that user to other services, enabling credential theft and lateral movement. Any unpatched installation of the listed Windows 10, Windows 11, and Windows Server 2008/2012/2016/2019 versions is exposed, which covers essentially every mainstream Windows estate current in late 2024. Exploitation is confirmed: the flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2024-11-12, researchers have reported Russian-linked attackers using it in phishing campaigns delivering RAT malware, and EPSS assigns an 84.1% probability of exploitation within 30 days, though no public proof-of-concept code is known. Do: Apply Microsoft's November 2024 Patch Tuesday security updates (or later cumulative updates) to all listed Windows 10/11 client and Windows Server versions; the KEV listing makes patching mandatory for US federal agencies. As interim mitigation, block outbound SMB/HTTP NTLM authentication to untrusted destinations (e.g., firewall outbound TCP 445 from endpoints) and, where feasible, restrict NTLM in favor of Kerberos via Group Policy. Hunt for phishing emails containing crafted files and for unexpected outbound authentication attempts from workstations, and rotate credentials for accounts that may have authenticated to untrusted hosts before patching. | 6.5 | 84% | KEV |
| masshundreds of millions of Windows 10/11 endpoints and Windows Server 2008-2019 instances worldwide |
Indicators of compromiseauto-extracted · verify before use · export allAll →
| Type | Indicator | Context |
|---|---|---|
| domain | gov.ua | m a compromised Ukrainian government server ("doc.osvita-kp.gov[.]ua") that prompts recipients to renew their academic certifi |
Full article449 words · extracted from thehackernews.com · click to collapse
Ravie LakshmananNov 14, 2024Malware / Vulnerability
A newly patched security flaw impacting Windows NT LAN Manager (NTLM) was exploited as a zero-day by a suspected Russia-linked actor as part of cyber attacks targeting Ukraine.
The vulnerability in question, CVE-2024-43451 (CVSS score: 6.5), refers to an NTLM hash disclosure spoofing vulnerability that could be exploited to steal a user's NTLMv2 hash. It was patched by Microsoft earlier this week.
"Minimal interaction with a malicious file by a user such as selecting (single-click), inspecting (right-click), or performing an action other than opening or executing could trigger this vulnerability," Microsoft revealed in its advisory.
Israeli cybersecurity company ClearSky, which discovered the zero-day exploitation of the flaw in June 2024, said it's been abused as part of an attack chain that delivers the open-source Spark RAT malware.
"The vulnerability activates URL files, leading to malicious activity," the company said, adding the malicious files were hosted on an official Ukrainian government site that allows users to download academic certificates.
The attack chain involves sending phishing emails from a compromised Ukrainian government server ("doc.osvita-kp.gov[.]ua") that prompts recipients to renew their academic certificates by clicking on a booby-trapped URL embedded in the message.
This leads to the download of a ZIP archive containing a malicious internet shortcut (.URL) file. The vulnerability is triggered when the victim interacts with the URL file by right-clicking, deleting, or dragging it to another folder.
The URL file is designed to establish connections with a remote server ("92.42.96[.]30") to download additional payloads, including Spark RAT.
"In addition, a sandbox execution raised an alert about an attempt to pass the NTLM (NT LAN Manager) Hash through the SMB (Server Message Block) protocol," ClearSky said. "After receiving the NTLM Hash, an attacker can carry out a Pass-the-Hash attack to identify as the user associated with the captured hash without needing the corresponding password."
The Computer Emergency Response Team of Ukraine (CERT-UA) has linked the activity to a likely Russian threat actor it tracks as UAC-0194.
In recent weeks, the agency has also warned that phishing emails bearing tax-related lures are being used to propagate a legitimate remote desktop software named LiteManager, describing the attack campaign as financially motivated and undertaken by a threat actor named UAC-0050.
"Accountants of enterprises whose computers work with remote banking systems are in a special risk zone," CERT-UA warned. "In some cases, as evidenced by the results of computer forensic investigations, it may take no more than an hour from the moment of the initial attack to the moment of theft of funds."
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2024/11/russian-hackers-exploit-new-ntlm-flaw.html