Malicious PDF — malware analysis report

Static analysis result for SHA-256 81c8132a9b0ef00b…

MALICIOUS

PDF

86.9 KB Created: 2021-07-30 17:05:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 555f64dc4aab131ff63e7af71dda09e7 SHA-1: e525793339a80577a3dfe582060f0735384ff177 SHA-256: 81c8132a9b0ef00b1f5576ff6f0f173e9d0e32a3b64d93d65c11616da13e38ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier. It contains numerous links pointing to potentially compromised WordPress sites and other disposable hosting, indicating a link farm designed to redirect users. The presence of embedded URLs and the nature of the heuristics suggest an attempt to distribute malicious content or phish for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/373b6a9233b75dc26842c55c91dc5023/noxaxazenol.pdf In PDF document text
    • http://artechq8.com/beta/uploads/files/jawolalelodejer.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160876e1184f24---gagatikajaxi.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/450e4048b7d69d77b1cf6a67d886a771/54730186364.pdfIn PDF document text
    • https://hkparkkonutlari.com/image/files/zikejajusafe.pdfIn PDF document text
    • http://trendymamy.pl/userfiles/file/faxod.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ba57f0ac789---94301857175.pdfIn PDF document text
    • https://blugarden.eu/file/50338861982.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/ed012dddf8e29eab7a9ee082312edeab/97426549338.pdfIn PDF document text
    • http://hillhouseclassof1961.com/clients/c/c9/c9b049383fb65e98d0a4dcab6c176392/File/kulagisopevijiluwovoro.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/14db091556306200121e12f49d8566c6/13675715974.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/25835486068.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16100968390cc0---57760384649.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076e9066f52d---95946538786.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/tuvarod.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/omem4j5qudpsu56iga3vdj48ne/6145552977.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/66230694722.pdfIn PDF document text
    • http://xn--b1adbbbaeqjtsflbfms0e.xn--p1ai/pict/file/22261513272.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/sodikedefatog.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/16071d66ef3e0b---40842401284.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b0367816150---22118727995.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/43303425809.pdfIn PDF document text
    • https://amoslodge10.org/ckfinder/userfiles/files/vapunizekurexubi.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/ss1as3bil41t23as0n9afts5e7/mogexonezokusesad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=medidas+de+cancha+de+voleibol+playaPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC1 10724 bytes
SHA-256: 00497d4dd16704616abe3b8393ffd7578b573befa33b2e566d32db2def65d5f2
font_01_sfnt_off00010818.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10818 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001202a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1202A 17772 bytes
SHA-256: 74f302d73fcc8d52943616a5eb26beb1135e8d60f705ba1dcebb4a5bf45acf95