Malicious PDF — malware analysis report

Static analysis result for SHA-256 168cf1059c09ed0c…

MALICIOUS

PDF

74.7 KB Created: 2021-09-16 19:53:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3b755d2dae31d882767718e67bc8cf1b SHA-1: 2091520927a57ecdf07ca16955322e475046523e SHA-256: 168cf1059c09ed0c7c49d41bb4ecd6c008a439dcb4fc6ddc043fe3830016f808
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites. The document body is heavily obfuscated and unreadable, but the presence of numerous embedded URLs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://massimomoroni.it/userfiles/files/tidenaguwukatumalibul.pdf In PDF document text
    • http://kristiankutschera.de/userfiles/file/1888351427.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131da0c194cd---xevafariluwozomibebisifa.pdfIn PDF document text
    • http://packturf.fr/files/7819767176.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/5de0744a8eee5823c5cfa8e064c2b603/25852495107.pdfIn PDF document text
    • https://wilocom.ro/ckfinder/userfiles/files/rilulitexegakurugerojudit.pdfIn PDF document text
    • https://123natura.com/stockages/files/zosowuduv.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/wubovulebuf.pdfIn PDF document text
    • http://stadion-zarya.ru/ckfinder/userfiles/files/93850837343.pdfIn PDF document text
    • http://arucax.am/user_images/file/purokevosuxisex.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/202195148558529.pdfIn PDF document text
    • http://galerie45.com/userfiles/file/domowejubijozewa.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/gv0bv6pe5q8m2f1p0643k1vmqo/vixilebokoludet.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/22358721798.pdfIn PDF document text
    • http://bayanairag.com/uploads/userfiles/files/21590195364.pdfIn PDF document text
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/5219445569.pdfIn PDF document text
    • http://zussobrance.sk/grafika/dokumenty/lodatine.pdfIn PDF document text
    • http://www.enfersalus.com/ckfinder/userfiles/files/66529374328.pdfIn PDF document text
    • http://sissonne.hu/editor_up/dutubobuzejininun.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/67778692640.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles/files/80396440202.pdfIn PDF document text
    • http://rideco.hu/upload/file/59298590338.pdfIn PDF document text
    • https://prosaison.fr/userfiles/files/vagarefanuwezabud.pdfIn PDF document text
    • http://em-mould.com/ckfinder/userfiles/files/vajedokikosisorufojexosa.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/ganixelexogemu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=juegos+para+android+download+freePDF 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_off0000be73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d68a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD68A 10752 bytes
SHA-256: f20cfcb4dcd1555441784d55450de84c432cf0c794ace26f7eacff81e38f65a3
font_02_sfnt_off0000ef39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF39 17696 bytes
SHA-256: b9c730c78147e0bf83f92461b5db71058c61f3353beaf7c2329d27708db1d2b3