Malicious PDF — malware analysis report

Static analysis result for SHA-256 c57b21a7a874968c…

MALICIOUS

PDF

91.5 KB Created: 2021-09-16 17:24:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2b2ec483312701dfec38a3e34119b494 SHA-1: c670fc549818dd297e86715f6d7f7b8b27f9c56a SHA-256: c57b21a7a874968c35b090e7ccfd4296a3f7741f22a4f98e674c99be2c15c4e3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document's purpose is to host numerous links on disposable domains, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the presence of embedded URLs and the link farm nature strongly suggest an intent to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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://stacjaregeneracja.pl/userfiles/file/bizixudovar.pdf In PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161426165c0760---37021693771.pdfIn PDF document text
    • http://keacg.com/upload/files/furigelepukawewapetataju.pdfIn PDF document text
    • http://h04ydivan.ru/userfiles/file/73301887458.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/23164637333.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/tedagilalepuxobeja.pdfIn PDF document text
    • http://studioaeditecne.it/userfiles/file/48754769250.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/folaxoketefetijuletawipez.pdfIn PDF document text
    • http://downtowncincyhotels.com/core_degree/admin/images/cms_imagesfiles/65571031103.pdfIn PDF document text
    • https://pasarantogel.com/contents/files/85626939371.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/37162864426.pdfIn PDF document text
    • http://tpdw.pl/userfiles/file/40847219249.pdfIn PDF document text
    • https://ht-cooling-j3t.com/contents/files/lezotiwexegefegurugulegod.pdfIn PDF document text
    • http://dreambeauty.kr/upload/fckeditor/file/jevedasip.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/zewovek.pdfIn PDF document text
    • http://gianenricofabro.com/userfiles/files/23829067630.pdfIn PDF document text
    • http://psychologadamczak.pl/userfiles/file/rewunilexusasiz.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/74982805939.pdfIn PDF document text
    • http://bettaletroom.com/file_media/file_image/file/82369040965.pdfIn PDF document text
    • http://pr-jam.com/ckfinder/userfiles/files/lonafafizapetobani.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/files/45002222275.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/adedc1c45e7290f1e10d869e4d552768/luletabefekekupu.pdfIn PDF document text
    • https://childprotectionindia.com/lexcyberia/userfiles/files/nitesisukanefulim.pdfIn PDF document text
    • https://bloomland.com/sites/bloomland.com/files/jatutirabapijiwimoxak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=react+native+run+android+choose+emulatorPDF 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_off0000fb1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB1C 20016 bytes
SHA-256: e29e00b0cf4b28debf2b24bb686d98cdcc99bf6d536bfc51953eb2365ee12602
font_01_sfnt_off00012fb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FB5 10848 bytes
SHA-256: 711dc3a73be69d3716b1d7770d9b92e0a4ac6828351e2c1ce5ea8b6643a8ae17
font_02_sfnt_off00014894.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14894 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1