Malicious PDF — malware analysis report

Static analysis result for SHA-256 e513bcf6905c4ab0…

MALICIOUS

PDF

70.0 KB Created: 2021-09-28 05:12:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 9577395793616ea0028c1fd63d65571d SHA-1: 68af8fe2d54f3ca9ddb4cf56f48d7c20d698bcd6 SHA-256: e513bcf6905c4ab08468089048004237a3a77b72f61477258dd02fc89bd1d63c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV and an ML classifier as malicious. It contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains, indicating a phishing or malware distribution attempt. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically points to this behavior, suggesting the document's primary purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://cructi.ru/uplcv?utm_term=the+walking+zombie+2+apk+download PDF link annotation
    • http://theexplorerthai.com/userfiles/files/69747433008.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/jexegedirujidex.pdfIn PDF document text
    • http://s13cf5ef.alojamientovirtual.com/ropadefutbolbarata/userfiles/file/93987831756.pdfIn PDF document text
    • http://vpsystem.com/files/fck/futiribafizepevixudat.pdfIn PDF document text
    • https://atrax.hr/files/tidoruwuxixupafamexafewu.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1613693f1735bc---pivudowonok.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/21382556707.pdfIn PDF document text
    • https://www.antoniopopolizio.it/ckfinder/userfiles/files/xuxetiwi.pdfIn PDF document text
    • http://ticaproduce.com/ckfinder/userfiles/files/zetexanujuxesosimutas.pdfIn PDF document text
    • http://hutbephottaihaiphong24h.com/upload/files/jukakofojuwipi.pdfIn PDF document text
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/10130731459.pdfIn PDF document text
    • https://intrastorg.com/userfiles/file/1130383832.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/44777063520.pdfIn PDF document text
    • http://sanphamhanquocymy.com/uploads/files/28580461162.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/zusisagusubezak.pdfIn PDF document text
    • http://homokkepek.hu/editor_up/63888824292.pdfIn PDF document text
    • https://www.mppoa.cloudlinesystems.com/assets/ckfinder/userfiles/files/dajuniruz.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/9253852441.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/wivoperirurubiduvu.pdfIn PDF document text
    • https://www.cygnusdvlp.in/nitdurgapur/uploads/editorUploads/userfiles/files/letovosagamimej.pdfIn PDF document text
    • http://satakantaresort.com/user_img/files/41563034548.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/sukojiloti.pdfIn PDF document text
    • https://deesudcoolingtower.com/userfiles/file/88690344967.pdfIn PDF document text
    • http://dogable.de/userfiles/file/4793305878.pdfIn PDF document text
    • 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_off0000b385.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB385 15024 bytes
SHA-256: 618779f60bda2a780ea6f7f5a25eaa06ab2fca74590185f25d08d968838e553a
font_01_sfnt_off0000d977.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD977 10932 bytes
SHA-256: a9f377ecf648a338374ad45c1e56eb3e482aad274502bbe8a69e540c0e9b7731
font_02_sfnt_off0000f238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF238 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1