Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6b3bb2b1a151591…

MALICIOUS

PDF

85.3 KB Created: 2021-09-13 07:17:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 42452fb6fb04d3a097cc6f67169fcba4 SHA-1: 9784f104934ae54d4cab2570ad13221850c2c64e SHA-256: d6b3bb2b1a1515915aa3c9478f228990c6e5c332fbc6c7df7c178f4197e4f809
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting and form a link farm, a common tactic for phishing or distributing further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and embedded links suggest it's designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://megalabsrl.it/userfiles/files/35926779029.pdf In PDF document text
    • https://shen-su.eu/gfx/userfiles/files/ridoduwa.pdfIn PDF document text
    • http://stisk.com/file/tabapugosasinagevux.pdfIn PDF document text
    • https://romalasergroup.com/userfiles/files/9923809588.pdfIn PDF document text
    • http://findingthegrey.com/userfiles/file/69133874289.pdfIn PDF document text
    • http://optikametuje.cz/userfiles/file/98353080368.pdfIn PDF document text
    • http://stmrcstvm.com/userfiles/file/68916811474.pdfIn PDF document text
    • http://ptk-tent.ru/userfiles/file/xejupiwoseminorosutini.pdfIn PDF document text
    • https://istocdukkan.com/userfiles/files/bipuporuwomoxakaxokul.pdfIn PDF document text
    • http://pantryscan.com/123cars/imagefck/file/71391046949.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/file/30058841291.pdfIn PDF document text
    • http://gruppocaminiti.it/userfiles/files/21680358759.pdfIn PDF document text
    • https://fond.ru/userfiles/file/95666635708.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/23592329537.pdfIn PDF document text
    • http://monarchiaerembolt.hu/tmp/gowigefunekedojob.pdfIn PDF document text
    • http://pnlestari.com/visitbali/image/files/bemiwofovogudotu.pdfIn PDF document text
    • http://vlajamo.cz/images/file/63617216751.pdfIn PDF document text
    • https://ngusacdon.com/upload/files/xujupodanonigevuz.pdfIn PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/45833623665.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/nebusuzuxuwuratifiz.pdfIn PDF document text
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210908_985549E5F825378D.pdfIn PDF document text
    • http://proleague.dk/userfiles/file/65157230723.pdfIn PDF document text
    • http://klpa.net/userData/board/file/nuzetuvolawufetegun.pdfIn PDF document text
    • http://greenbiotech.vn/uploads/userfiles/file/dobulukodetulexof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=exam+warriors+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_off0000ebb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB6 10452 bytes
SHA-256: d38f9610e0c976f608151133a001bfb8286c4997e0adc5d1e6f12600e7435291
font_01_sfnt_off00010373.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10373 17212 bytes
SHA-256: c8074f171ec89c89c452cdb5888a27db0b1622450b83f1505890b113330abe90
font_02_sfnt_off00012fca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FCA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1