Malicious PDF — malware analysis report

Static analysis result for SHA-256 5718b31d4e2b8b46…

MALICIOUS

PDF

79.3 KB Created: 2021-09-20 16:59:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 11b1c5d1bbd4d197db629c3d6c3bbd7b SHA-1: bbf4727de16f2137932c4814b63e262fc64d9555 SHA-256: 5718b31d4e2b8b4606742eb4fd744a4e81a14de503bfc01f1cb897c3f9060407
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by ML classifiers and ClamAV as malicious, with a high heuristic score for being a link farm on disposable hosting. It contains numerous embedded URLs pointing to other PDF files on distinct domains, suggesting a distribution or phishing campaign. The 'utm_term' parameter in one of the URLs indicates a potential tracking mechanism for user engagement.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://asremajazi.com/uploads/files/bagudakekikunegobu.pdf In PDF document text
    • https://majorsagilekvaros.hu/uploads/file/94518098804.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/22878708991.pdfIn PDF document text
    • https://geya99.com/ckfinder/userfiles/files/kenasojizeta.pdfIn PDF document text
    • http://apisicul.com/userfiles/files/50249260308.pdfIn PDF document text
    • http://theponghop.com/upload/files/93173059838.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/kebuf.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/4071343753.pdfIn PDF document text
    • https://egyseg.eu/ckfinder/userfiles/files/dodud.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/dekebesage.pdfIn PDF document text
    • http://sm300159.agchost.com/userfiles/files/46045619886.pdfIn PDF document text
    • https://huuphongplastic.vn/uploads/images/files/pokabixejufubip.pdfIn PDF document text
    • https://dollarplus98.com/images/upload/files/43234673853.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16144b50ee2049---xesoriwapiromufijop.pdfIn PDF document text
    • http://cpils.com/userfiles/file/pexitoxagunomo.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613dffce80aa7---devojipisu.pdfIn PDF document text
    • http://newbiesites.com/userfiles/file/80166660178.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/75415341580.pdfIn PDF document text
    • https://threadworx.com/thread/admin/uploads/file/87321327442.pdfIn PDF document text
    • http://originalavto.ru/userfiles/file/36586373748.pdfIn PDF document text
    • http://www.lebedosapartotel.com/data/yukle/files/86771341924.pdfIn PDF document text
    • https://avukat.dnsaktif.net/upload/files/41107327951.pdfIn PDF document text
    • https://prokoncept.hu/admin/blogfck/image/file/41753274620.pdfIn PDF document text
    • http://membranekeyboard.pl/_data/file/xivajakuvivebufijam.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/pojodexipuxumopikokelalab.pdfIn PDF document text
    • http://silver.jo/ckfinder/blanc/files/42931499142.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=network+setting+code+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_off0000ce62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e674.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE674 18588 bytes
SHA-256: c4745620f3e44afe40a01ca259bef222b76b54d825201c5afea27028ee9a1f83
font_02_sfnt_off0001169b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1169B 10760 bytes
SHA-256: dcd5c49d69da4b8f66f531a9a2c176cfa2fda4122365238aaf07a9c654b83a3c