Introduction
Russian state-sponsored hackers [5] [6] [8], associated with the Main Intelligence Directorate (GRU) and known as APT28 or Fancy Bear, have developed an innovative Wi-Fi hacking technique called the “Nearest Neighbor Attack.” This method allows them to infiltrate a target’s Wi-Fi network by first compromising a device on a nearby vulnerable network, effectively bypassing advanced security measures such as multi-factor authentication (MFA) [7].
Description
Russian state-sponsored hackers associated with the Main Intelligence Directorate (GRU), known as APT28 or Fancy Bear, have developed a novel Wi-Fi hacking technique termed the “Nearest Neighbor Attack.” This sophisticated method allows them to breach the Wi-Fi network of a target by first compromising a laptop on a vulnerable network in a nearby building. By utilizing that computer’s antenna [4], the hackers can access the intended victim’s network without needing to be physically close to their targets, effectively bypassing advanced security measures [7], including multi-factor authentication (MFA) [1] [3] [5] [6] [7] [8].
This technique was first documented during an investigation into a network breach affecting a Washington [3] [4], DC-based company [5], referred to as Organization A [8], which was engaged in projects related to Ukraine. This investigation coincided with geopolitical tensions prior to Russia’s invasion of Ukraine in early 2022 [3]. The attack process began with APT28 acquiring valid credentials for the target’s corporate Wi-Fi network through password-spraying attacks on a public-facing service. However, the presence of MFA complicated direct access over the public internet. To circumvent this, APT28 adapted their strategy by compromising a nearby organization’s Wi-Fi network, which lacked MFA protection for its VPN [7]. They accessed a device with both wired and wireless capabilities located within range of Organization A, utilizing a dual-homed system to connect to the target’s enterprise Wi-Fi without needing MFA.
Cybersecurity experts noted that the attackers connected to specific wireless access points in a conference room of Organization A [8], indicating that the threat originated externally rather than from within the organization [1]. Initial assessments suggested that the attackers physically approached the building to execute the attack [1]. However, further investigation revealed that they compromised a device across the street [1], demonstrating the mechanics of the nearest neighbor attack [1]. This innovative approach allowed APT28 to gather crucial intelligence related to the Ukraine conflict effectively, utilizing methods such as “living-off-the-land” and exploiting zero-day vulnerabilities.
Once inside Organization A’s network, the attackers moved laterally using a remote desktop connection (RDP) from an unprivileged account to search for systems of interest and exfiltrate data. They executed servtask.bat to extract Windows registry hives [6], compressing them into a ZIP archive for exfiltration while relying on native Windows tools like Cipher.exe to erase evidence and evade detection by endpoint response systems. APT28 likely exploited the CVE-2022-38028 vulnerability in the Windows Print Spooler service on Organization A’s network [6], allowing them to escalate privileges before executing a critical payload [6]. The incident was identified on February 4, 2022 [6], by cybersecurity firm Volexity [2] [4] [6] [7], which discovered a server compromise linked to activities concerning Ukraine. Although Volexity could not initially attribute the attack to a known actor [6], a subsequent Microsoft report revealed indicators of compromise (IoCs) that overlapped with Volexity’s findings [6], confirming the involvement of APT28.
This attack vector presents significant challenges for cybersecurity professionals [3], necessitating a reassessment of Wi-Fi network security [3]. Recommendations include implementing MFA for Wi-Fi access [7], limiting Wi-Fi range [3] [6] [8], obfuscating network names [3], and segregating wireless networks from Ethernet-based ones to mitigate such breaches [7]. The Nearest Neighbor Attack demonstrates that proximity access operations [6], which typically require physical closeness to a target [6], can be conducted remotely [6] [8], reducing the risk of detection [6] [7] [8]. Despite advancements in security measures like MFA [6], enterprise Wi-Fi networks should be treated with the same caution as other remote access services [6]. Organizations engaged in activities contrary to Russian interests are encouraged to adopt a heightened cybersecurity posture and consult the US Cybersecurity & Infrastructure Security Agency (CISA) Shields Up program for comprehensive guidance on preparing for, responding to [5], and mitigating the effects of Russian state-sponsored cyberattacks [5].
Conclusion
The Nearest Neighbor Attack exemplifies the evolving nature of cyber threats, highlighting the need for robust cybersecurity measures. Organizations must reassess their Wi-Fi security protocols, incorporating strategies such as MFA, network segmentation [3], and range limitation to mitigate potential breaches. As cyber threats continue to advance, maintaining a proactive and vigilant cybersecurity posture is essential, particularly for entities involved in activities that may attract state-sponsored adversaries. Consulting resources like the CISA Shields Up program can provide valuable guidance in preparing for and responding to such sophisticated cyberattacks.
References
[1] https://www.pandasecurity.com/en/mediacenter/what-is-a-nearest-neighbor-attack/
[2] https://itsecuritywire.com/quick-bytes/russian-cyberspy-group-apt28-enters-target-organizations-network-through-wifi/
[3] https://thesecmaster.com/blog/russian-hackers-launch-sophisticated-wi-fi-attacks-using-neighbors-as-a-covert-en
[4] https://soylentnews.org/index.pl?issue=20241127
[5] https://fieldeffect.com/blog/fear-thy-neighbors-they-could-be-apt-28
[6] https://www.isss.org.uk/news/hackers-breach-us-firm-over-wi-fi-from-russia-in-nearest-neighbor-attack/
[7] https://i-hls.com/archives/126720
[8] https://twit.tv/posts/transcripts/security-now-1002-transcript
