Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fb5b66056db5b40…

MALICIOUS

PDF

79.8 KB Created: 2021-09-16 20:33:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 85fc4cde0b736d8a9251d86c3dc64f1e SHA-1: 1c699cc0daa05ede67405361c0de5f4f18e181fe SHA-256: 5fb5b66056db5b40bb85ae2e4bbb08e8584c0905edfe6c577546dc495cddf60d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicating a high number of distinct hosts and links. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the structure and URL patterns are indicative of a malicious PDF designed to redirect users to potentially harmful 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 http://yeongwonenc.com/userfiles/file/72243780441.pdf In PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/43903616570.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/rogamugusakagemipexiloke.pdfIn PDF document text
    • http://grupopiscis.com/upload/files/85435089357.pdfIn PDF document text
    • http://infosierra.es/images/editor/zukuve.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/kamixopadudabowixob.pdfIn PDF document text
    • https://www.zochrot.org/ckfinder/userfiles/files/punupijupemekavikolud.pdfIn PDF document text
    • https://cauthinh.com/luutru/files/kenidijesevimoripowun.pdfIn PDF document text
    • http://romento.com/uploaded_files/userfiles/files/53814258555.pdfIn PDF document text
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/30697212375.pdfIn PDF document text
    • http://sushimura1.com/uploads/files/lelunatixowoxurumemaluj.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/guzip.pdfIn PDF document text
    • http://mim2010.ru/userfiles/file/sexamowejositeb.pdfIn PDF document text
    • https://bruceautoservice.com/files/file/57907699383.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/9a173136ff522559da72581aa5bfc336/43187049344.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/41658680826.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161403b985ee20---zovujajobogoxijewef.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/42583603175.pdfIn PDF document text
    • http://oralrem.kz/ckfinder/userfiles/files/81314942360.pdfIn PDF document text
    • https://izr.fr/files/xupetusobimekaxibu.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/popekorisugikudaxow.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/pikagu.pdfIn PDF document text
    • http://cdn.eagle.mn/uploads/userfiles/files/17812049917.pdfIn PDF document text
    • http://chaputlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/79642893044.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=spirited+away+piano+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_off0000d734.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD734 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF46 16304 bytes
SHA-256: 3a85f3ef20dc38e20308b03e2f263d268723bd273e3af4e07a53e346a986737e
font_02_sfnt_off00011968.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11968 10552 bytes
SHA-256: c14956c0018674fca5e72d5b75b374b7c33ffcdadd6ed7263111abc7deb916bb