Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4b24836cf2066c3…

MALICIOUS

PDF

69.8 KB Created: 2021-09-24 22:21:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: e2a09f0875fd6a4f0189616f16e8977d SHA-1: a2d816bd9f2c08c004557e7ffe988b9f8d947bf4 SHA-256: b4b24836cf2066c3e29068132fadf4fd0bd5cd68a8c569ca4a7b5361e01ac8a3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a significant portion pointing to potentially malicious domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were directly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution vector, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://qhzs88.com/admin/fckeditor_upfiles/file/2021090604452580554.pdf In PDF document text
    • http://muzycznescyzoryki.pl/userfiles/file/45003305382.pdfIn PDF document text
    • https://culturasiapamplona.com/guiarte_userfiles/files/nesuxet.pdfIn PDF document text
    • http://2018.letnifestiwal.pl/ckfinder/userfiles/files/lozazirawusoluvox.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16135ade3321b2---59100804036.pdfIn PDF document text
    • http://neboskreb-irk.ru/uploads/userfiles/files/gobulomina.pdfIn PDF document text
    • https://praktijk.zorglink.nl/ckfinder/userfiles/files/xepibudewalemobadedo.pdfIn PDF document text
    • http://appartementslisa.it/an3_Uploads/file/43743158253.pdfIn PDF document text
    • http://kimsanghun.com/upload/userfiles/file/2021923225426788.pdfIn PDF document text
    • https://cowik.pl/upload/beravesoke.pdfIn PDF document text
    • https://artgallery.devctn.com/ckfinder/userfiles/files/42665608157.pdfIn PDF document text
    • https://volandovia.it/public/fileeditor/file/68145137785.pdfIn PDF document text
    • http://terrietanaka.com/library/files/dujajari.pdfIn PDF document text
    • https://dsverano.com/UserFiles/File/74285748501.pdfIn PDF document text
    • http://innotec-industrie.be/userfiles/file/34821595817.pdfIn PDF document text
    • http://ridendo.cz/files/file/80003576489.pdfIn PDF document text
    • http://findusafranchise.com/files/files/zapoxemevolutakugen.pdfIn PDF document text
    • http://datev.hu/ckfinder/userfiles/files/jozitidopema.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/pixuv.pdfIn PDF document text
    • https://projectmine.hu/ckfinder/userfiles/files/29744319222.pdfIn PDF document text
    • https://vibangnhadat.com/uploads/files/mirorokad.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/fijobej.pdfIn PDF document text
    • http://eskuvoiiranytu.hu/blog/file/44709594361.pdfIn PDF document text
    • http://klhl.com/userfiles/file/sokonebiwibesobaxorad.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/jawokifabi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=billie+eilish+documentary+123moviesPDF 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_off0000b1f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1F4 14544 bytes
SHA-256: c83631662a0ea76b30d6c787f7dc427229e21365efd3faa1bdb4d7225cb74699
font_01_sfnt_off0000d5ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE06 11312 bytes
SHA-256: f81390070f1226a2c3ccfcf5beb44c4e5519d0d25770f3f5b30878da0725d0fe