Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8222518d390d77a…

MALICIOUS

PDF

75.4 KB Created: 2021-09-19 19:52:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ad831eda0f25a14519f698438563ccd3 SHA-1: 8a5a2e3391a53c5fa6d7dcafd5e4686e34d50b0c SHA-256: c8222518d390d77a1ebe1f19b9b84c4aed43d929ec28a4eb339ceec6879fa42d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as containing a link farm and was classified as malicious by an ML model and ClamAV. The heuristics indicate that the document is designed to host numerous links, many of which point to disposable or compromised domains, suggesting a phishing or malware distribution scheme. While no scripts were directly extracted, the presence of embedded URLs and the nature of the link farm heuristics point towards an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://tradingphrases.net/userfiles/files/bigunivuxewanev.pdf In PDF document text
    • http://ex2010.com/uploadfile/file/2021091109235373499.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/11346815416.pdfIn PDF document text
    • http://antonio-pelella.eu/userfiles/files/98172091989.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16144581c8af62---potaxaruxevupugajowewas.pdfIn PDF document text
    • http://partner-support.net/user_data/userfiles/files/zenomike.pdfIn PDF document text
    • http://letsbelegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/90634290402.pdfIn PDF document text
    • http://yuc-fac.com/uploadfiles/20210918021617.pdfIn PDF document text
    • http://tamilannuaire.com/var/www/vhosts/vps296430.ovh.net/tamilannuaire.com/images/file/terofarazej.pdfIn PDF document text
    • http://tsrmvolontari.it/userfiles/files/vilozepixub.pdfIn PDF document text
    • https://safetypadlocks.eu/eurostyl/photos/file/61418136103.pdfIn PDF document text
    • http://yasairamenbar.com/uploads/files/31306064155.pdfIn PDF document text
    • http://obraz-tlt.ru/userfiles/file/fimepuxumebuz.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613798a58f7f6---tifekagakexamem.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161417badb874e---97749365398.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/pabuxiwesuduzetusovus.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/74811119882.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/zotepokurojitomevifugare.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/8219220802.pdfIn PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/16966302397.pdfIn PDF document text
    • http://weilandensemble.nl/ckfinder/userfiles/files/77533705186.pdfIn PDF document text
    • https://greenlakecruises.com/ckfinder/userfiles/files/99961208847.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=focus+ios+app+for+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_off0000c322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC322 10416 bytes
SHA-256: a6f895af5f48a58adc56f60c2695a5d9a79faf8347ef9f49556833d957b55601
font_01_sfnt_off0000dac6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC6 17632 bytes
SHA-256: 9ab15a16b501d944246638798ff76228a139f57a80ab1b483b188ed5e21b36d5
font_02_sfnt_off00010828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10828 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1