Russian APT28 Hackers Targeting High
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2023-23397 | Zero-Click Elevation of Privilege in Microsoft Outlook (Forced NTLM Credential Leak) CVE-2023-23397 is an elevation of privilege vulnerability in Microsoft Outlook caused by improper input validation (CWE-20) combined with authentication bypass via spoofed authentication data on the channel (CWE-294), allowing an attacker to force Outlook to authenticate to an attacker-controlled SMB/WebDAV server. It is triggered when Outlook processes a crafted email or calendar object — for example a meeting or task reminder whose sound property points to an attacker-supplied UNC path — and requires no user interaction. That authentication exchange leaks the victim's NTLM credential hash, which the attacker can crack offline or relay to authenticate as the victim and access resources such as Exchange mailboxes, effectively escalating privileges. Affected software spans Microsoft 365 Apps, Microsoft Office (including the Long Term Servicing Channel), and Microsoft Outlook, which are deployed across enterprises, governments, and militaries worldwide. It is actively exploited in the wild — added to CISA's Known Exploited Vulnerabilities catalog on 2023-03-14 with a 97.4% EPSS — and Microsoft has warned of exploitation by Russia-aligned threat actors in campaigns against government and military mail servers, with patches shipped in Microsoft's March 2023 security updates. Do: Apply Microsoft's March 2023 security updates to Microsoft 365 Apps, Office/LTSC, and Outlook immediately, per CISA's required action. As interim mitigation, enable Extended Protection for Authentication or add accounts to the Protected Users group to block the NTLM credential leak, and audit calendar and task reminder sound properties for UNC paths (Microsoft published an audit/cleanup script for this) while watching for unexpected outbound SMB/WebDAV connections from hosts running Outlook. | 9.8 | 97% | KEV |
| masson the order of hundreds of millions of users (Outlook ships with Microsoft Office/Microsoft 365, the dominant enterprise and government email suite) | |
| CVE-2023-38831 | Code Execution in RARLAB WinRAR via Crafted ZIP File/Folder Name Confusion RARLAB WinRAR before 6.23 mishandles ZIP archives that contain a benign file (such as a JPG) alongside a folder with the same name, causing the folder's contents - which can include malicious executable files - to be processed when the user merely attempts to view the benign file. By sending a crafted ZIP archive, an attacker gains arbitrary code execution on the victim's machine with the user's privileges. Because the flaw is local (AV:L) and requires user interaction, risk is limited to Windows systems running an unpatched copy of WinRAR, while machines without the tool are unaffected. The bug was actively exploited in the wild from April through October 2023, including by government-backed actors (APT28), SideCopy attacks on Indian government entities, ransomware operations, and trading-account theft campaigns, and it was added to CISA's Known Exploited Vulnerabilities catalog on 2023-08-24. Do: Upgrade all Windows systems running WinRAR to version 6.23 or later, which fixes this flaw; if patching is not immediately possible, treat ZIP files from untrusted sources with caution and check archives for duplicate file/folder names before opening. Given KEV listing with known ransomware use and public proof-of-concept exploits, hunt for compromise by reviewing whether unexpected executables or scripts ran when ZIP archives were opened, and apply vendor mitigations per CISA's required action or discontinue use if mitigations are unavailable. | 7.8 | 98% | KEV ransomware PoC ×4 |
| masshundreds of millions of users/installations worldwide (WinRAR is one of the most widely installed Windows archive utilities) |
Indicators of compromiseauto-extracted · verify before use · export allAll →
| Type | Indicator | Context |
|---|---|---|
| domain | webhook.site | login pages mimicking Microsoft Outlook that are hosted on webhook[.]site URLs, a pattern previously attributed to the group. In a |
Full article706 words · extracted from thehackernews.com · click to collapse
Russian state-sponsored actors have staged NT LAN Manager (NTLM) v2 hash relay attacks through various methods from April 2022 to November 2023, targeting high-value targets worldwide.
The attacks, attributed to an "aggressive" hacking crew called APT28, have set their eyes on organizations dealing with foreign affairs, energy, defense, and transportation, as well as those involved with labor, social welfare, finance, parenthood, and local city councils.
Cybersecurity firm Trend Micro assessed these intrusions as a "cost-efficient method of automating attempts to brute-force its way into the networks" of its targets, noting the adversary may have compromised thousands of email accounts over time.
APT28 is also tracked by the broader cybersecurity community under the names Blue Athena, BlueDelta, Fancy Bear, Fighting Ursa, Forest Blizzard (formerly Strontium), FROZENLAKE, Iron Twilight, ITG05, Pawn Storm, Sednit, Sofacy, and TA422.
The group, believed to be active since at least 2009, is operated by Russia's GRU military intelligence service and has a track record of orchestrating spear-phishing campaigns bearing malicious attachments or strategic web compromises to activate the infection chains.
In April 2023, APT28 was implicated in attacks leveraging now-patched flaws in networking equipment from Cisco to conduct reconnaissance and deploy malware against select targets.
The nation-state actor, in December, came under the spotlight for exploiting a privilege escalation flaw in Microsoft Outlook (CVE-2023-23397, CVSS score: 9.8) and a code execution bug in WinRAR (CVE-2023-38831, CVSS score: 7.8) to access a user's Net-NTLMv2 hash and use it to stage an NTLM relay attack for gaining unauthorized access to mailboxes belonging to public and private sector firms.
An exploit for CVE-2023-23397 is said to have been used to target Ukrainian entities as early as April 2022, according to a March 2023 advisory from CERT-EU.
It has also been observed leveraging lures related to the ongoing Israel-Hamas war to facilitate the delivery of a custom backdoor called HeadLace, alongside striking Ukrainian government entities and Polish organizations with phishing messages designed to deploy bespoke implants and information stealers like OCEANMAP, MASEPIE, and STEELHOOK.
One of the significant aspects of the threat actor's attacks is the continuous attempt to improve its operational playbook, fine-tuning and tinkering with its approaches to evade detection.
This includes the addition of anonymization layers such as VPN services, Tor, data center IP addresses, and compromised EdgeOS routers to carry out scanning and probing activities. Another tactic entails sending spear-phishing messages from compromised email accounts over Tor or VPN.
"Pawn Storm has also been using EdgeOS routers to send spear-phishing emails, perform callbacks of CVE-2023-23397 exploits in Outlook, and proxy credential theft on credential phishing websites," security researchers Feike Hacquebord and Fernando Merces said.
"Part of the group's post-exploitation activities involve the modification of folder permissions within the victim's mailbox, leading to enhanced persistence," the researchers said. "Using the victim's email accounts, lateral movement is possible by sending additional malicious email messages from within the victim organization."
It's currently not known if the threat actor themselves breached these routers, or if it is using routers that were already compromised by a third-party actor. That said, no less than 100 EdgeOS routers are estimated to have been infected.
Furthermore, recent credential harvesting campaigns against European governments have used bogus login pages mimicking Microsoft Outlook that are hosted on webhook[.]site URLs, a pattern previously attributed to the group.
In a sign that the group in no stranger to pivoting and shifting tactics when needed, an October 2022 phishing campaign singled out embassies and other high-profile entities to deliver a "simple" information stealer via emails that captured files matching specific extensions and exfiltrated them to a free file-sharing service named Keep.sh.
"The loudness of the repetitive, oftentimes crude and aggressive campaigns, drown out the silence, subtlety, and complexity of the initial intrusion, as well as the post-exploitation actions that might occur once Pawn Storm gets an initial foothold in victim organizations," the researchers said.
The development comes as Recorded Future News revealed an ongoing hacking campaign undertaken by the Russian threat actor COLDRIVER (aka Calisto, Iron Frontier, or Star Blizzard) that impersonates researchers and academics to redirect prospective victims to credential harvesting pages.
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2024/02/russian-apt28-hackers-targeting-high.html