Malicious PDF — malware analysis report

Static analysis result for SHA-256 f14cd73e3331f040…

MALICIOUS

PDF

79.0 KB Created: 2021-09-10 20:17:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3dd8e13f5072fb228504d846abf577ba SHA-1: 81a867545b4a7f2ec55f56438875265890866f03 SHA-256: f14cd73e3331f0402c03943837272214d7f400ee9e3de4490eef12400ae5ef24
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to disposable hosting and are part of a link farm. This strongly suggests a phishing or malware distribution campaign. The ML classifier and ClamAV detection further confirm the malicious nature of the file, indicating it is likely a phishing or trojan variant.

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://crewmak.ru/uplcv?utm_term=pre+a1+starters+book+pdf PDF link annotation
    • https://psihodesk.ro/ckfinder/userfiles/files/40500536164.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad57b2b602---safebiwowura.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/3927451383.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/59712396592.pdfIn PDF document text
    • https://piauiaqui.com/ckfinder/files/guwefo.pdfIn PDF document text
    • http://emiem.pl/public/upload/ckfinder/userfiles/files/vidabetenogep.pdfIn PDF document text
    • http://mamnonsaokhue.vn/app/webroot/files/ckfinder/files/tibokonefagugezotejikuso.pdfIn PDF document text
    • http://objets.immoweiss.lu/userfiles/files/dofibarolov.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210908034734.pdfIn PDF document text
    • http://mikailang.com/userfiles/file/20210908025919_1321043811.pdfIn PDF document text
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/fazedu.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/63639352356.pdfIn PDF document text
    • http://bursaceyizgelinlik.com/images_upload/files/68773090299.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/tufemukonox.pdfIn PDF document text
    • http://abwmechanicsville.com/uploads/files/33806755370.pdfIn PDF document text
    • http://cathyourhair.nl/js/ckfinder/userfiles/files/72362897599.pdfIn PDF document text
    • http://lohoithaiduong.com/uploads/files/84127406628.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/pomozuxef.pdfIn PDF document text
    • http://www.520amis.com/upload/files/38757757280.pdfIn PDF document text
    • https://vnmmalta.com/userfiles/file/xizip.pdfIn PDF document text
    • http://le-nora.com/userfiles/file/20622984348.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/e6cf4065a8ca377223b78a5cddb24e62/47592251876.pdfIn PDF document text
    • http://alfatreyd-mebel.ru/archive/images/file/damopixesezewunezalajasef.pdfIn PDF document text
    • http://furnitura-syndicat.ru/ckeditor/ckfinder/core/connector/php/uploads/files/noxuxoxetaduvujik.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_off0000cfd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFD3 10532 bytes
SHA-256: add374a08b767a44e677df0ac6b9c2dcefb1eca2d6f3d38b84883642ff1761ce
font_01_sfnt_off0000e7d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ffe8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE8 17772 bytes
SHA-256: 10320b76711229ff1483033367ed727ad3e7a4fa5b4e6578aa555927777673fe