Malicious PDF — malware analysis report

Static analysis result for SHA-256 dec2daa33930f0f9…

MALICIOUS

PDF

81.4 KB Created: 2021-10-07 02:33:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a7c1b6c414d3eb63632614f3fa429794 SHA-1: c6961ec0c6dab704cd51b1165e504a3e77f44f19 SHA-256: dec2daa33930f0f9c0067e9d78ec61433790aea75aed286147b6169a32645e65
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs pointing to various PDF files hosted on different domains, indicating a link farm or distribution network. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this is not a legitimate document but rather a tool for SEO manipulation or to serve malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://bright-inter.com/file_media/file_image/file/sopodereresudabililetep.pdf In PDF document text
    • http://kstarsmall.net/userfiles/file///61649837168.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/kuwaxonorumabafina.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/mokezurado.pdfIn PDF document text
    • http://sutipatika.hu/userfiles/files/1229071350.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/48275214886.pdfIn PDF document text
    • http://darslaska.org/ckfinder/userfiles/files/jukapuzamet.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/6163408076.pdfIn PDF document text
    • http://naturabliskociebie.pl/userfiles/file/12501077192.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/wugemixopowagatobemobaxo.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/fukus.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/pakuzuxafefipivozakiraf.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/86654242321.pdfIn PDF document text
    • http://eubeer.vn/uploads/files/71876269687.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/movomigivajiwupos.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/mijufanevikasonigimenu.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/1117384802.pdfIn PDF document text
    • http://sgrappresentanze.eu/userfiles/files/87688672142.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aaefa8b566---nutopelavuxekapuka.pdfIn PDF document text
    • https://themalc.org/files/file/bevunuxikazubipemobedo.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/dalotiwipob.pdfIn PDF document text
    • http://duancanhotot.com/upload/files/wosise.pdfIn PDF document text
    • http://1hozain.ru/files/userfiles/files/80727719433.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613d07bbd496e---12341973423.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=manufacturing+feasibility+study+pdfPDF 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_off0000d8ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EA 17640 bytes
SHA-256: a5c9ae714c0c4dc5f8230a62da675a116c1042d1c6969d1f90d7f7ed03a3704f
font_01_sfnt_off000106d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D8 11020 bytes
SHA-256: 3f38ba6a23196ae5950448dd270135f469c1c95ed84f7f64a94bf6b9704eceaa
font_02_sfnt_off00012036.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12036 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1