Malicious PDF — malware analysis report

Static analysis result for SHA-256 99ccd3c22cf3a7fa…

MALICIOUS

PDF

87.5 KB Created: 2021-09-07 14:53:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-18
MD5: c2db792ae7b68bad3f95773d2bad04dd SHA-1: d5c40cbcdb3ee72664022b1331af598939571de1 SHA-256: 99ccd3c22cf3a7fa034814238e020350a77b92753931600133b337aa4e9569f2
154 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics and the overall structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5346

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
  • 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
  • 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://poorclarescork.ie/images/debudixeborogonoti.pdf In PDF document text
    • http://brlairport.com/images/file/jafopixikate.pdfIn PDF document text
    • http://rowadhr.com/app/webroot/upload/files/38177220670.pdfIn PDF document text
    • https://ngoctraithaibinhduong.com/uploads/news_file/pobarubegaxitamugimoketug.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b7e7cf90aa9---fupaxigapemejivakusifanaj.pdfIn PDF document text
    • https://cancelaria.pl/galeria/file/zuwenokaxifuwes.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/89217101383.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/sisawudikev.pdfIn PDF document text
    • https://menlopark.com/wysiwygfiles/file/nejavonofudarutunadupowe.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae89a8f046f---bakilepuzitugekutilud.pdfIn PDF document text
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/dagixonogefasugepewog.pdfIn PDF document text
    • http://viprealestatebrokers.com/userfiles/files/99978953126.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16089c2b18c2ee---25054259965.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c0effb5688e---75460148456.pdfIn PDF document text
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/12624bfb6e438722e5d5f74bf520969d/korusa.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/neninijexuvezulagaxesobe.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f6ea9da244c---61160546569.pdfIn PDF document text
    • http://evopizza.lt/ckfinder/userfiles/files/61376809198.pdfIn PDF document text
    • http://kwong-cheong.com/userfiles/93247884210.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/nujudosavanisajokuno.pdfIn PDF document text
    • http://rulada.by/upload/editor/files/69386592569.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/pibuvizedosejamezafax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=action+research+cycle+model+pdfPDF link annotation
    • 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_off00010213.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10213 10980 bytes
SHA-256: 218682e3e5e0c7f763b2c79c57a1617e7e5f7eb5bd7cfd71f8285f4ca4e4c41a
font_01_sfnt_off00011b66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B66 17260 bytes
SHA-256: 62e52dd4cece0a0863a8148512b412d57e49b28b695c3a3c68c2c4e900d56312
font_02_sfnt_off00014810.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14810 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1