Malicious PDF — malware analysis report

Static analysis result for SHA-256 849d8e783f743683…

MALICIOUS

PDF

81.6 KB Created: 2021-09-21 01:12:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: cc9ad2dbf784193949f9d5dcc0f759f7 SHA-1: 8da709e6bf6fbc8c6ce57fb0cff02fb4fdcda7dd SHA-256: 849d8e783f743683d6013dfe7c807fa4797a681a33c91816c7bd9807ede9825f
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple disposable domains and compromised CMS uploads, likely to host phishing pages or malware. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL analysis strongly suggest a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 http://tcsklife.com/filespath/files/20210921052443.pdf In PDF document text
    • http://kalikraft.com/images/file/nopunaro.pdfIn PDF document text
    • http://jumpinfit.it/userfiles/files/66477586288.pdfIn PDF document text
    • https://mami-m.com/Uploads/userfiles/files/11253139630.pdfIn PDF document text
    • http://chinhsuasolieu.com/media/files/49435089202.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/numuvoga.pdfIn PDF document text
    • http://studioprogettoarchitettura.eu/userfiles/files/duvebada.pdfIn PDF document text
    • http://poaglasses.com/uploads/files/202109101610512274.pdfIn PDF document text
    • https://hotnews.md/upload/userfiles/files/43380663072.pdfIn PDF document text
    • http://prograsifkalip.com/files/65755611827.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/81024400435.pdfIn PDF document text
    • http://generaldistco.com/images/file/11705538022.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210912180244.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/64249839242.pdfIn PDF document text
    • http://infosierra.es/images/editor/dajaz.pdfIn PDF document text
    • http://24horasnoar.com.br/ckfinder/userfiles/files/golebabebumovixaj.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135f860a3b81---25790470347.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16144b3981aa3e---51338024426.pdfIn PDF document text
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/31445085876.pdfIn PDF document text
    • http://englandmatchshirts.com/assets/file/65369257061.pdfIn PDF document text
    • http://intersonik.eu/upload/files/mupeduwiv.pdfIn PDF document text
    • http://villabrown.it/userfiles/files/puxefumizulukek.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/7djjq2f64jhtc9fgb1b37q34b1/tuzudejiju.pdfIn PDF document text
    • https://birsamundapark.in/userfiles/files/70233206067.pdfIn PDF document text
    • http://betheaskssd.com/flash/betheaskssd.com/file/66944939142.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161346a5785fe0---ruxolarupegaziwa.pdfIn PDF document text
    • https://anbuadidravidarmatrimony.com/ckfinder/userfiles/files/29658470308.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=open+amazon+links+in+amazon+app+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_off0000dba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA8 17356 bytes
SHA-256: 5fd89f128a90ee362c7c161f35798f549fdc46405edbf0f70a8088b86ddc6f9a
font_01_sfnt_off00010844.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10844 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001205b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205B 10632 bytes
SHA-256: 97093aea0bedbe5764ea9cf26072565dee6ce1c65f5ec9ef6f338bcca44ed3fb