Malicious PDF — malware analysis report

Static analysis result for SHA-256 157f9ce198527f0a…

MALICIOUS

PDF

71.6 KB Created: 2021-09-20 02:18:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f4d45eab7b705d6bbed5f90e6b138c84 SHA-1: 7584ee7fae3c59b0239f7aa1b7de164af63d4e30 SHA-256: 157f9ce198527f0a4be8a039ef6cd5e43bb792c7d179be5f2ff14bf2cdd14788
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and an ML classifier flagged it with high confidence. It contains embedded JavaScript and numerous external URIs pointing to suspicious domains, many of which are likely part of a link farm designed to redirect users. The presence of JavaScript suggests an attempt to execute malicious code, potentially to download further payloads or redirect the user to a phishing site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://cructi.ru/uplcv?utm_term=android+vpn+cracked PDF link annotation
    • https://swiz.eu/files/editor/merapesigowe.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/wazazafatatevivalefaxi.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/balivixulevigumozukisut.pdfIn PDF document text
    • http://reginahajo.hu/_user/file/sutojadixejaxivuzu.pdfIn PDF document text
    • http://armiikrajowej36.pl/public/upload/ckfinder/userfiles/files/33411758657.pdfIn PDF document text
    • http://headlinesdinerla.com/uploads/files/75861349465.pdfIn PDF document text
    • http://xn--90aoaidn.xn--p1ai/ckfinder/userfiles/files/nunejuwebebu.pdfIn PDF document text
    • http://marketypik.pl/zdjecia/fck/file/43050521050.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/votobok.pdfIn PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/77714204675.pdfIn PDF document text
    • http://rubivina.com/Images_upload/files/9107387982.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/d5058304fbc892f9bef73e4a836bcf5d/51402578993.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/94756035367.pdfIn PDF document text
    • https://borsalino.ro/imagini_ws/zusexizuwagipuruk.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1631073214.pdfIn PDF document text
    • http://markjfox.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/90622591528.pdfIn PDF document text
    • http://luijkzonwering.nl/image/file/derupimefuwi.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e94ace74b7---94961085092.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/50958158013.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/tofimupimelarox.pdfIn PDF document text
    • http://thibidi.vinadesign.info/uploads/images/files/dekofuzeki.pdfIn PDF document text
    • https://ghadir-eng.com/userfiles/files/judasaropesexibajotukogis.pdfIn PDF document text
    • http://roosprommenschenckelfoundation.nl/userfiles/file/livewatifomifexumiwev.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/67411380157.pdfIn PDF document text
    • https://www.thc.gda.pl/ckfinder/userfiles/files/zekidijixinub.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_off0000b703.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB703 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF1A 10336 bytes
SHA-256: 1e8c6c011af39de1a3ef6a13f906db65c1472c123551485d3c7695ca7b8c1da5
font_02_sfnt_off0000e684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE684 16376 bytes
SHA-256: 4817007a5f2ee853e2f35a6c71c3e21d9a3330c67fe8151baa4693361c28ea7f