Malicious PDF — malware analysis report

Static analysis result for SHA-256 266d9e1fa033a757…

MALICIOUS

PDF

69.4 KB Created: 2021-09-25 15:14:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a4bb775a78e8da13175a028610aa76b7 SHA-1: ee79e59d578755e779fa95ff3c39ee782a938acb SHA-256: 266d9e1fa033a75762ffad9f48a19ae4231386921d5322a06977ecd38703792a
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable domains, and one heuristic specifically flagged it as a 'link farm on disposable hosting'. This suggests the PDF's primary purpose is to redirect users to a network of sites, likely for SEO spam or to host further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/a7f80f267f34b46fd0ee63538a6c4f4a/23319202697.pdf In PDF document text
    • http://apartament-krokus.pl/userfiles/file/lukatezisaginagole.pdfIn PDF document text
    • http://feldbach-tourismus.at/files/gitafuzuvogawadopagema.pdfIn PDF document text
    • https://aiwcecckolkata.org/FCKeditor/file/rozedutema.pdfIn PDF document text
    • http://tdjl.com/uploadfile/file///2021090322004173.pdfIn PDF document text
    • http://globalsublimation.net/uploadfile/files/xobezulamulawabaj.pdfIn PDF document text
    • http://hzyixiangchem.com/upload/files/17916667249.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/sijugufelugediruluw.pdfIn PDF document text
    • http://alocainghien.com/uploads/userfiles/file/87371918085.pdfIn PDF document text
    • http://yilip.net/userData/board/file/24133435447.pdfIn PDF document text
    • http://speaklifeiamgreatness.com/files/files/sutumote.pdfIn PDF document text
    • https://www.luthier-auxerre.fr/ckfinder/userfiles/files/gonidewapivagiketawav.pdfIn PDF document text
    • http://creativetechno.in/userfiles/file/8719066784.pdfIn PDF document text
    • http://ikcem.org/userfiles/file///41974213109.pdfIn PDF document text
    • http://wxeina.com/userfiles/files/pugegu.pdfIn PDF document text
    • https://gencerenerji.com/resimler/files/76852967101.pdfIn PDF document text
    • http://shosholoza.de/file/wewetuwisinimere.pdfIn PDF document text
    • https://motodubai.com/uploaded_images/files/pevifur.pdfIn PDF document text
    • http://punaide.com/userfiles/files/88841150400.pdfIn PDF document text
    • http://szjg.hu/images/file/93536351252.pdfIn PDF document text
    • http://maychebiengoduykhuong.com/media/ftp/file/85532783442.pdfIn PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/puxizewerepijidogitekilo.pdfIn PDF document text
    • https://tbsva.org/Upload/files/20210903044355.pdfIn PDF document text
    • https://implant-drill.com/userfiles/file/tixijunufupobobebumozusoz.pdfIn PDF document text
    • https://alrukn.co/userfiles/files/48313098573.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/watupapunajuradavurekadul.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=tekken+3+apk+obb+downloadPDF 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_off0000b135.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB135 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c94c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC94C 10380 bytes
SHA-256: 7f70f9740d0cf5bb45eaee5deb000230c1f00593a140876d03de9109dbb2c461
font_02_sfnt_off0000e0be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0BE 15584 bytes
SHA-256: 42fa150ea521478fb6e3b1ac5f4fa7315581f1218368c2d0fe9f0489d1a3ee20