Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1fc779a1c4b13d2…

MALICIOUS

PDF

68.5 KB Created: 2021-09-24 14:23:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c79fa9fd6f80ce1eb2c9e0b8c34ee91c SHA-1: d3e49f025927f4686352a7ad3a9856dea5cd5ebf SHA-256: b1fc779a1c4b13d22be6190fff03f9720cf975aaca2c91a8eb3b2570c5224925
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of external URIs and link farm heuristics suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://tessuno.com/upload/files/614c62247607a.pdf
    • http://preiss.at/upload_files/files/67762411013.pdf
    • https://777mto.net/contents/files/garug.pdf
    • https://2ruoteexpo.it/ckfinder/userfiles/files/wanusop.pdf
    • http://libron.pl/fckupload/assets/file/nomifegarepuvepovipod.pdf
    • http://j1ent.com/userfiles/file/20210907183144.pdf
    • http://dpsszczytno.pl/photo/file/zigiles.pdf
    • http://villa-carlshorst.de/sites/default/files/file/48597870669.pdf
    • https://holcom-wd.com/webroot/img/files/71996977906.pdf
    • http://ahknchem.com/upload/files/fidekesad.pdf
    • http://geoscan.it/userfiles/files/jajuvugun.pdf
    • https://kebecelectrique.com/upload/editor/file/23995360007.pdf
    • http://wacommerce.net/home/integrity/public_html/ckfinder/userfiles/files/zovusozexatiwote.pdf
    • https://khanoomhoteli.com/basefile/khanoomhotelicom/files/luzurovirenixusovodimob.pdf
    • https://gentrilieu.vn/userfiles/file/wizipulula.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1612f987120f95---34309745426.pdf
    • https://timavoshipsupply.it/userfiles/file/5568802700.pdf
    • https://groupburuemas2.com/contents/files/35883891531.pdf
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/f9211ac713f007f1a9d2a2f190bc7ae3/kugiwetapizesitasirosugoj.pdf
    • https://havadisname.com/upload/ckfinder/files/61015354616.pdf
    • http://immobilier-valence-agen.com/userfiles/file/86596082728.pdf
    • http://sunpix.ru/img/lib/file/kukop.pdf
    • https://yocarbroker.com/upload/ckfinder/files/73063244989.pdf
    • http://7seapharmtech.com/Uploadfiles/files/31706460863.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/161302c1a8860a---nazarekuzekimo.pdf
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/6343b21bfd5ff52daacbc8b882aa155e/83752490628.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=fts+apk+obb+download
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b08d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB08D 16792 bytes
font_01_sfnt_off0000c89f.bin
c393d724d1a37005b2751a46c315df4317539d81cee9375a978f768ecfbf33ed
pdf-font-stream PDF embedded font (sfnt) at offset 0xC89F 14664 bytes
font_02_sfnt_off0000ed79.bin
c2801e488eaa2b3c65216a0efb27ade5a3113d121d6b22e96c421f052067fc0a
pdf-font-stream PDF embedded font (sfnt) at offset 0xED79 10356 bytes