Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb7fd3a1f21fec58…

MALICIOUS

PDF

70.2 KB Created: 2021-09-09 14:26:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2ecddfa7a51e1a693e045a5b50c6ea0c SHA-1: eceb672ffc0f4522d75a3c435a29cf7be78b38a4 SHA-256: cb7fd3a1f21fec584a38f4633859288841ebef5a579a7554bbe3c3d9fd2b2010
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1071.001 Web Protocols

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and numerous external URIs suggests the document is designed to exploit vulnerabilities or lure users into downloading further malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a tactic of using numerous small, disposable domains to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://wastran.ru/uplcv?utm_term=all+rhombus+shapes PDF link annotation
    • http://noithatphathuy.com/Images_upload/files/viwuxetaz.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/22918913572.pdfIn PDF document text
    • https://stomatoloska-ordinacija-rijeka.com/files/bumexafakamibex.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/maperulupipezigizaxir.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/mosamama.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/09/file/rakube.pdfIn PDF document text
    • https://kristaldicarlo.com/userfiles/file/55063453457.pdfIn PDF document text
    • https://gotoko.com/cmsv2/upload/files/66280678855.pdfIn PDF document text
    • http://thuonghieutoancau.vn/uploads/files/wowudigaxunuguwumabunik.pdfIn PDF document text
    • https://truongthanhco.vn/webroot/img/files/fakafog.pdfIn PDF document text
    • http://edilcfcostruzioni.com/userfiles/files/56807613612.pdfIn PDF document text
    • http://hijoin.hu/editor_up/zepetunodidopijikaru.pdfIn PDF document text
    • http://www.como-grup.ro/fisiere/file/ranerafemu.pdfIn PDF document text
    • http://burmeseburmilla-allevamento.com/userfiles/files/27129625384.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/rvi5hgh58lgeqr4m8ets95depv/zinoduniwatumesubinebu.pdfIn PDF document text
    • http://fabriquetextil.com/js/new/fckeditor/userfiles/file/20860949935.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/fazulojiborolinuxo.pdfIn PDF document text
    • https://ecoverservice.be/gallery/file/88187299794.pdfIn PDF document text
    • https://norservis.info/files/files/jobezafixogow.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161374e85570e8---74635207964.pdfIn PDF document text
    • http://dongsimkindergarten.com/upload/files/fugiveweluro.pdfIn PDF document text
    • http://pibar.tw/uploads/files/202109030653407624.pdfIn PDF document text
    • http://hidropro.hu/upload/50355236945.pdfIn PDF document text
    • https://www.rt9.rspo.org/ckfinder/userfiles/files/30542577330.pdfIn PDF document text
    • 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_off0000b311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB311 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB23 16248 bytes
SHA-256: 23cc06cd11cee8ccb3252ea9bc9b84774b2658089032223b763706e223874d14
font_02_sfnt_off0000f3ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AD 10444 bytes
SHA-256: b21e2a6a73a8574248e8845f14aaff02573d00b4d3b99cc490f6771ffdd380e2