Malicious PDF — malware analysis report

Static analysis result for SHA-256 77a6b15f973f4eaa…

MALICIOUS

PDF

85.8 KB Created: 2021-08-28 15:14:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 0487a27b03fd5e6d2120d7fd2525feff SHA-1: c471fdea7c95912c2104df8ae7879bdaebc7f0e2 SHA-256: 77a6b15f973f4eaa1b47e13a7cd01212c818ecd2901c9d12cfb8d68a9c1e4072
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high probability of malicious intent. It functions as a link farm, presenting numerous URLs that point to other PDF files hosted on compromised WordPress sites and disposable domains. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics confirms this behavior, suggesting the document is designed to lure users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a0958057a1b---winovirinate.pdf In PDF document text
    • http://puppies-4u.com/clients/e/e7/e7f09595da74c05d2059c741134300d2/File/fuxexusopajukadarotaverik.pdfIn PDF document text
    • https://urbanlivin.lu/userfiles/files/29821643977.pdfIn PDF document text
    • http://intproplaw.com/admin/uploads/file/lupumix.pdfIn PDF document text
    • https://rrr71.ru/upload_picture/kinupetevupabatonojunomok.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/48927092295.pdfIn PDF document text
    • https://evergreencans.com/userfiles/file/dabuxazasasutikulelaver.pdfIn PDF document text
    • https://prairieroseclothiers.com/FCKeditor/file/65299843745.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1609de81fb0e46---79132871392.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/36142260326.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847377b38a7---nedovavirimimeron.pdfIn PDF document text
    • https://airshow-bg.com/file/liboxobetulalu.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/q5bcko1ea71q6v9gecfl6brqis/woxarodogafomofavexuji.pdfIn PDF document text
    • https://porterbrothersltd.com/app/webroot/uploads/49979967561.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/dj74rm2onv76ge9n17elcti4l4/jokuruzo.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/dt6qamhvvr2hhmid7red5kgju3/pabemapomadujanoz.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/kmco0nbk2v2ue0vm7jmc4fecj2/61266530975.pdfIn PDF document text
    • https://kozmetikadunakeszi.hu/userfiles/file/refasuzalotugekowede.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=burn+out+protocolPDF 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_off0000ec55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC55 9964 bytes
SHA-256: 659144fcd1fa9ed264996497f5c41b90c0a2ee1215c7bbbaaf56cee95cf63ab5
font_01_sfnt_off00010289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10289 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A9B 18392 bytes
SHA-256: 7a90011c6a09103d4b52bdc36866242dfd59b24d62ed719c88a97468c4a2ba94