Malicious PDF — malware analysis report

Static analysis result for SHA-256 0635cb2c0dccf82c…

MALICIOUS

PDF

68.0 KB Created: 2021-09-01 21:46:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 7eda11e5017679033bb848b30a1c67ad SHA-1: afb2a26a759beb2a455117a5b581b390202c031d SHA-256: 0635cb2c0dccf82cd1f34a4d342a219fc8e12f887a6b2d83da35c3ee9cfaff39
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and uses an image-based lure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://infrive.ru/uplcv?utm_term=example+of+my+personal+timeline PDF link annotation
    • http://bulk-supplies.com/userfiles/file/dibomuwopebosomim.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/dozavugapuroximu.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/37906002305.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/fcbm13dvhlm6foiuk70ic576mp/58005865332.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/83067737568.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/649a168940468d11e065457c12cde1b7/62814490760.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/e37c046e2c679b192a9b5f65f3f3b445/73840604152.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/ae1ae62d628c72b0a0805419107a4f55/94282623800.pdfIn PDF document text
    • http://tms-operation.com/upload/files/37110826127.pdfIn PDF document text
    • http://opalsolar.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160713366c706a---78392819069.pdfIn PDF document text
    • http://hyundaiokla.com/uploads/files/kitexutuw.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/juroledediritijemudi.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/b006243da95299406ba7b3053fbbd0e9/gedazuxuwafe.pdfIn PDF document text
    • https://cristalensi.com/public/File/zikevemikesajulaxuma.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/d3a1he12oaj1brmfcf7jallqoa/44954455038.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/vulekogugelavelugad.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/f02526475d578f415ffafe8ef6851022/94381509548.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/31096911208.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac73a03ac06---xidivu.pdfIn PDF document text
    • https://rowanmkt.com/Uploads/ckfinder/userfiles/files/3331328958.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/vibisuvopimolidedozutaje.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/ximazipamuromakakix.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1623069909.pdfIn PDF document text
    • 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_off0000b01c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB01C 10716 bytes
SHA-256: e0e8b8a493b04eb33afe0822d7d1b7ba68429437ee8005ec953756bfd5b4f8e0
font_01_sfnt_off0000c8ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8BA 14012 bytes
SHA-256: 9061b1f511be935a48c69a5bbd447d512013d45ba0a717080795c2cad27c5ca9
font_02_sfnt_off0000eaec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1