{"id":310,"date":"2025-02-04T23:55:23","date_gmt":"2025-02-04T18:25:23","guid":{"rendered":"https:\/\/www.securis360.com\/blog\/?p=310"},"modified":"2026-02-18T06:21:38","modified_gmt":"2026-02-18T06:21:38","slug":"russian-cybercrime-groups-exploiting-7-zip-flaw-to-bypass-windows-motw-protections","status":"publish","type":"post","link":"https:\/\/securis360.com\/blog\/russian-cybercrime-groups-exploiting-7-zip-flaw-to-bypass-windows-motw-protections\/","title":{"rendered":"Russian Cybercrime Groups Exploiting 7-Zip Flaw to Bypass Windows MotW Protections"},"content":{"rendered":"\n

A critical security flaw in 7-Zip<\/strong>, tracked as CVE-2025-0411<\/strong> (CVSS score: 7.0), was found to be leveraged by Russian cybercrime groups to bypass Windows Mark-of-the-Web (MotW) protections<\/strong> and execute arbitrary code on targeted systems. The issue was resolved in 7-Zip version 24.09<\/strong>, released in November 2024<\/strong>.<\/p>\n\n\n\n

According to Trend Micro<\/strong> security researcher Peter Girnus<\/strong>, the flaw was actively exploited through spear-phishing campaigns<\/strong> utilizing homoglyph attacks<\/strong> to spoof file extensions, tricking both users and Windows into executing malicious files.<\/p>\n\n\n\n

Exploitation in Cyber Espionage Campaigns<\/strong><\/h3>\n\n\n\n

Reports indicate that CVE-2025-0411<\/strong> was weaponized to target both governmental and non-governmental organizations in Ukraine<\/strong>, aligning with the ongoing Russo-Ukrainian conflict<\/strong>. The flaw enabled attackers to bypass security checks, facilitating a cyber espionage<\/strong> campaign.<\/p>\n\n\n\n

Microsoft\u2019s MotW security feature<\/strong> is designed to prevent unverified files from executing without further scrutiny via Microsoft Defender SmartScreen<\/strong>. However, this vulnerability was exploited by double archiving malicious payloads using 7-Zip<\/strong>, effectively concealing the threat.<\/p>\n\n\n\n

Technical Breakdown of CVE-2025-0411<\/strong><\/h3>\n\n\n\n

Prior to 7-Zip version 24.09<\/strong>, the application failed to properly enforce MotW protections<\/strong> on files contained within nested (double-encapsulated) archives<\/strong>. This oversight allowed attackers to craft malicious archives<\/strong> containing scripts or executables that bypass Windows security mechanisms.<\/p>\n\n\n\n

Attackers first double-archived<\/strong> malicious content, making it appear as legitimate files. Then, they distributed these deceptive archive files via phishing emails<\/strong>, leading unsuspecting users to unknowingly execute SmokeLoader<\/strong>, a well-known loader malware frequently used in attacks against Ukraine.<\/p>\n\n\n\n

Attack Chain & Infection Methodology<\/strong><\/h3>\n\n\n\n

The attack sequence was first identified on September 25, 2024<\/strong>, with malicious emails containing specially crafted archive files<\/strong>. The attack flow included:<\/p>\n\n\n\n

    \n
  1. Phishing Emails:<\/strong> The campaign involved phishing emails containing homoglyph-manipulated ZIP archives<\/strong> masquerading as Microsoft Word documents<\/strong>.<\/li>\n\n\n\n
  2. Compromised Email Accounts:<\/strong> Attackers used previously compromised Ukrainian government and business email accounts<\/strong> to make phishing messages appear credible.<\/li>\n\n\n\n
  3. Archive Execution:<\/strong> When the ZIP archive was opened, it triggered the execution of a .URL shortcut file<\/strong>, leading victims to an attacker-controlled server<\/strong> hosting another ZIP file.<\/li>\n\n\n\n
  4. SmokeLoader Deployment:<\/strong> The second ZIP contained a SmokeLoader executable disguised as a PDF document<\/strong>, which, when opened, initiated the infection.<\/li>\n<\/ol>\n\n\n\n

    Targeted Entities & Security Implications<\/strong><\/h3>\n\n\n\n

    At least nine Ukrainian government agencies<\/strong> and other organizations were affected, including:<\/p>\n\n\n\n

      \n
    • Ministry of Justice<\/strong><\/li>\n\n\n\n
    • Kyiv Public Transportation Service<\/strong><\/li>\n\n\n\n
    • Kyiv Water Supply Company<\/strong><\/li>\n\n\n\n
    • City Council<\/strong><\/li>\n<\/ul>\n\n\n\n

      Girnus noted that smaller local government bodies<\/strong> were particularly vulnerable, as they often lack robust cybersecurity resources<\/strong> compared to larger government agencies. Cybercriminals exploit these organizations as stepping stones<\/strong> to infiltrate broader networks.<\/p>\n\n\n\n

      Mitigation Measures & Security Recommendations<\/strong><\/h3>\n\n\n\n

      Given the active exploitation<\/strong> of CVE-2025-0411<\/strong>, organizations are strongly advised to:<\/p>\n\n\n\n

      \u2705 Update 7-Zip to version 24.09<\/strong> to patch the vulnerability.
      \u2705 Enhance email security<\/strong> by implementing phishing filters and blocking suspicious attachments.
      \u2705 Restrict execution of files<\/strong> from untrusted or external sources.<\/p>\n\n\n\n

      Girnus emphasized the importance of cyber resilience<\/strong>, particularly for under-resourced government agencies, urging them to strengthen defenses<\/strong> against emerging cyber threats.<\/p>\n","protected":false},"excerpt":{"rendered":"

      A critical security flaw in 7-Zip, tracked as CVE-2025-0411 (CVSS score: 7.0), was found to be leveraged by Russian cybercrime groups to bypass Windows Mark-of-the-Web (MotW) protections and execute arbitrary code on targeted systems. The issue was resolved in 7-Zip version 24.09, released in November 2024. According to Trend Micro security researcher Peter Girnus, the […]<\/p>\n","protected":false},"author":1,"featured_media":968,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[15,16,61,17],"class_list":["post-310","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news","tag-cybercrime","tag-cybersecurity","tag-data-privacy","tag-data-protection"],"_links":{"self":[{"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/posts\/310","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/comments?post=310"}],"version-history":[{"count":1,"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/posts\/310\/revisions"}],"predecessor-version":[{"id":969,"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/posts\/310\/revisions\/969"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/media\/968"}],"wp:attachment":[{"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/media?parent=310"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/categories?post=310"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/securis360.com\/blog\/wp-json\/wp\/v2\/tags?post=310"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}