Malicious PDF — malware analysis report

Static analysis result for SHA-256 834a01a250f70af6…

MALICIOUS

PDF

68.8 KB Created: 2021-10-01 19:23:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: b71b675a8d1432fa5d3456afab0c7016 SHA-1: 23591cde50075698d8c65d561b756a7348881c7a SHA-256: 834a01a250f70af64671a2cc0f9703a6f0fe39b6ad55e4f08d6869d6c78c0819
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting and are structured as link farms, indicating a phishing or malicious redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the heuristic PDF_SEO_DISPOSABLE_LINK_FARM and the sheer volume of external links point towards a campaign to drive users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://sakem.org/userfiles/files/71377424680.pdf In PDF document text
    • http://virtuozi.ru/sites/all/sites/virtuozi.ru/files/9125730644.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/161319247195f9---xitigenepuvebev.pdfIn PDF document text
    • https://www.miotsukushi.or.jp/system/ckfinder/userfiles/files/gogeloz.pdfIn PDF document text
    • http://hytechcommunications.com/userfiles/file/mogewo.pdfIn PDF document text
    • http://zhuxintrading.com/uploads/ckfinder/files/20210927/16327119814303.pdfIn PDF document text
    • http://cokhihoaiduc.com/uploads/files/67231150045.pdfIn PDF document text
    • http://kanomax-nsk.ru/images/73782214872.pdfIn PDF document text
    • https://landviewdesign.com/userfiles/file/bemodajibagiwowuxe.pdfIn PDF document text
    • http://cngwalk.com/fckeditor/userfiles/image/71263718430.pdfIn PDF document text
    • https://mekongtransport.com/upload/userfiles/files/60985131126.pdfIn PDF document text
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109122246209500.pdfIn PDF document text
    • http://poddertradingandindustries.com/userfiles/file/bitaralobewizelut.pdfIn PDF document text
    • https://alharithiforcameras.com/ckfinder/userfiles/files/keguwuj.pdfIn PDF document text
    • http://cappellastudio.it/userfiles/files/88780667388.pdfIn PDF document text
    • http://volkshilfe-vlbg.at/images/content/files/97752331855.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/45a3f96904f53021619b16e1959e0f29/tobifisibeno.pdfIn PDF document text
    • http://rejs2013.cycling-recycling.eu/imgturysta/files/21723962224.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/65041269746.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/sugojipolifubodoguvifapu.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/93370389907.pdfIn PDF document text
    • http://thehedgerowchronicles.com/ckfinder/userfiles/files/wilokiwajeb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=amiibo+nfc+codes+androidPDF 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_off0000b047.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB047 14676 bytes
SHA-256: 979ca799a810c9ab55341dd24a2f9aad4b51a3170734547990b56ddd91eb1464
font_01_sfnt_off0000d529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD529 10612 bytes
SHA-256: 7faf4a64e2dda6e03d5ac3a4f12bd0849c2ceffb3b7084eaf296884673634d89
font_02_sfnt_off0000ed67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED67 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1