Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f78e8f480ae049f…

MALICIOUS

PDF

81.1 KB Created: 2021-09-19 17:34:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4ce7ffa20402b106679e0aa69c41b089 SHA-1: 7d720d9b2d76619f3df13c4ddc54724637e62e8f SHA-256: 8f78e8f480ae049f3d9de35442ad467d5dd73cd003cbfe9c48063d975e932fa9
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 PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates it's part of a link farm designed to host many PDFs on disposable domains. While no executable scripts were extracted, the presence of numerous embedded URLs and the nature of the heuristics suggest a phishing or content-distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://kasintorn.com/images/upload/files/97190221535.pdf In PDF document text
    • http://stoka-saarlouis.de/userfiles/file/bezuzipi.pdfIn PDF document text
    • https://profitaler.com/UserFiles/file/nupewavidekafof.pdfIn PDF document text
    • http://gsxr.hu/userfiles/file/figipisezimow.pdfIn PDF document text
    • https://viktorina.ledoritulys.lt/files/33123358826.pdfIn PDF document text
    • http://profitoolinfo.ru/ckfinder/userfiles/files/30825615108.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/kifujutijab.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/161370e70839f6---46849713617.pdfIn PDF document text
    • http://4chan.ro/UserFiles/file/19366856317.pdfIn PDF document text
    • https://ceccardolj.ro/userfiles/file/tivedotalukusepusovegi.pdfIn PDF document text
    • https://hotellemaritime.com/hotel/upload/files/siwesisawuroniwi.pdfIn PDF document text
    • http://hennel.hu/sources/elemek/file/nininubamoreris.pdfIn PDF document text
    • http://tokyoto.pl/UserFiles/file/zixelamizisaxanares.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/25d83a8e3236ca570f35a7c585ce1268/jobotuduxagi.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021090702073755.pdfIn PDF document text
    • http://nb-magnet.com/upload/files/97466140406.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/gexivifaparolef.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/44983316878.pdfIn PDF document text
    • http://aeusjtu.pretty-match.com/upload/files/37179722013.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/47499528906.pdfIn PDF document text
    • https://masukpt1.com/contents/files/64867729732.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/36896914823.pdfIn PDF document text
    • https://lemarko.com/userfiles/file/34855204431.pdfIn PDF document text
    • http://xfswchem.com/upload/files/gawonuseroxaxipote.pdfIn PDF document text
    • http://thehedgerowchronicles.com/ckfinder/userfiles/files/fukuvenatalugi.pdfIn PDF document text
    • http://nujhimachal.in/img/uploads/files/bekixokezakapepede.pdfIn PDF document text
    • http://ketphatthinh.vn/upload/files/2767308899.pdfIn PDF document text
    • http://kaies.net/upfiles/210907005719028091peps9x.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=print+artist+for+androidPDF 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_off0000d83b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD83B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f052.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF052 10172 bytes
SHA-256: 3e2cfe049317d582b441755e1e65a03adfaa631efdabeb553dc0fde2dda13868
font_02_sfnt_off0001072b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072B 18320 bytes
SHA-256: f0c147d8e82229c91dff13fb97f1778805cc6028f09292648c0cf36c9f22ca20