Malicious PDF — malware analysis report

Static analysis result for SHA-256 c565500550cc2cbd…

MALICIOUS

PDF

84.7 KB Created: 2021-09-10 03:07:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 9778055f3579f5a0c07ffec544a3f31a SHA-1: b62a2b42687a088ac024132f36be915943d6bf45 SHA-256: c565500550cc2cbda321e59bcc02736b34a23f7d3e1aed61c0671bce64c7e9d4
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://na-bytecek.cz/UserFiles/File/92317202321.pdf In PDF document text
    • https://innovaciones-plasticas.com/imagenes_cont/sitio/documentos/rujaku.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/30810055404.pdfIn PDF document text
    • http://1-sanya.com/blog_images/blog_/file/13255406608.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/52094361971.pdfIn PDF document text
    • http://i-akparat.kz/ckfinder/userfiles/files/64329439767.pdfIn PDF document text
    • https://ekoelprom.pl/public/images/editor/file/remuroganulijavemodom.pdfIn PDF document text
    • http://vhz.cz/user-files/dofilobejujajadikofosabam.pdfIn PDF document text
    • http://photou.cc/ckfinder/userfiles/files/bupojunaxovufamodenusinel.pdfIn PDF document text
    • http://archbot.pl/files/file/72901445463.pdfIn PDF document text
    • https://araprinter.com/ckfinder/userfiles/files/tajujiroxajolojo.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343e9d10279---kudegesigiximujemiselise.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/81292677365.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613a87de7705e---98293831197.pdfIn PDF document text
    • https://marblobaths.com/app/webroot/img/files/virepudokenazakupifarulop.pdfIn PDF document text
    • http://rosesrealtyhomes.com/userfiles/files/pakasigigezudibijukafogon.pdfIn PDF document text
    • http://huarui-bio.com/upload/files/74623821691.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/44275926429.pdfIn PDF document text
    • https://ambulatorioveterinariosismondi.eu/file/2244124832.pdfIn PDF document text
    • https://nepalonetours.com/userfiles/files/lalilavozozezapala.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/91324177715.pdfIn PDF document text
    • https://orderpoet.com/ckfinder/userfiles/files/70586999726.pdfIn PDF document text
    • http://collectifff.be/imgdb/accueil/files/14427858090.pdfIn PDF document text
    • http://sadiqandsons.com/userfiles/files/5966720381.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=disable+internet+on+android+phonePDF 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_off0000e01d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE01D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF834 10632 bytes
SHA-256: d867f999d36481067f7bc231081bbf587c87299035ab1fa5c10b05a6f2de2f85
font_02_sfnt_off00011029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11029 19980 bytes
SHA-256: 816d3d70c470e78693b18f3dfe4096286e9a32f3602b2d8b4052c8f56be8dfe5