Malicious PDF — malware analysis report

Static analysis result for SHA-256 2d1edbe82bd24334…

MALICIOUS

PDF

80.1 KB Created: 2021-09-12 09:18:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8becafd65694d03a3b3cf38147bf790a SHA-1: 101ed821472fbdb42c4bc956a13ecac112c394e2 SHA-256: 2d1edbe82bd24334930c18a08dc52c07eb4d1c4e8a30110f3c7942cad5f28cd8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct hosts. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm heuristic point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://vekosgroup.ru/userfiles/file/17866798777.pdf In PDF document text
    • https://kligi.viart.lt/ckfinder/userfiles/files/gimivixemipe.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/jajiwiziredopiput.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/zagimuzesabikuvufewawudos.pdfIn PDF document text
    • http://www.biogreeno.com/cms/ckfinder/userfiles/files/sivenena.pdfIn PDF document text
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/vizix.pdfIn PDF document text
    • http://hongphuc.vn/userfiles/file/24072252535.pdfIn PDF document text
    • http://aallergy.friend-match.com/upload/files/77695360288.pdfIn PDF document text
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/foser.pdfIn PDF document text
    • http://grafiport.com/userfiles/file/63947514545.pdfIn PDF document text
    • http://dlabiura.kbo.pl/ckfinder/userfiles/files/32606910670.pdfIn PDF document text
    • http://www.vishalsahni.com/public/ckfinder/userfiles/files/loxamalija.pdfIn PDF document text
    • https://burgas-remonti.com/userfiles/file/sumexaf.pdfIn PDF document text
    • http://ltpbetel.ro/userfiles/file/dokim.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/zalapawijazamutisapibi.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/31787226964.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613b8967cf2ce---51996245947.pdfIn PDF document text
    • http://buyyoutubesubscribers.com/ci/userfiles/files/veruwawesevezebu.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/161304a9fe1d1c---fosunanup.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210910_0D355B92284A6529.pdfIn PDF document text
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/27806310526.pdfIn PDF document text
    • http://italianopizzeria-pg.com/uploads/files/gugixor.pdfIn PDF document text
    • http://brixtontaxi.com/survey/userfiles/files/26052544907.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=dls+2019+app+downloadPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/95438797334.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_off0000d24d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD24D 10512 bytes
SHA-256: 02305c06930bb16e01b6ec84d8e224896bff0a8e0a94af0f6bc47b393d6a1923
font_01_sfnt_off0000ea73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010285.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10285 18756 bytes
SHA-256: 82a228b36eb1d930217cc25df2b32511e4db1e8021a5757ebe9a64508708373f