Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8357c32f1b198cf…

MALICIOUS

PDF

75.4 KB Created: 2021-10-01 11:45:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 1bd158cc60d2b2baa1eec94bf98d5dbe SHA-1: 94de589c449ddb0f0b882d06538249e71d6cbbea SHA-256: a8357c32f1b198cfe64910a402266be715dc14c59b28be20a909de00d9f91de1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. This script likely redirects the user to one of the numerous external URLs found in the sample, which are often used for phishing or to download further malicious payloads. The ML classifier and ClamAV detection strongly indicate malicious intent.

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://wastran.ru/uplcv?utm_term=vrai+jeux+android PDF link annotation
    • http://stringladies.cz/userfiles/ledobivarizebafomag.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/4869947098.pdfIn PDF document text
    • http://lpc2529.com/piceditor/file/temagane.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/wifofadidisojutakedu.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/52265930117.pdfIn PDF document text
    • http://zhongyuemedia.com/filespath/files/20210902011310.pdfIn PDF document text
    • http://www.dagmarsvendova.cz/admin/js/ckfinder/userfiles/files/47036740805.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/89lrtl9eku83lbdrk2kjq82gnu/tuluvejipiwusif.pdfIn PDF document text
    • https://faktxeber.com/resimler/files/68283476964.pdfIn PDF document text
    • http://top-rubber.com/admin/fckeditor/editor/filemanager/connectors/upload/file/dabajifisux.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/45193212804.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/goxonidetil.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/posiletejamilenagive.pdfIn PDF document text
    • https://listapp.in/ci/userfiles/files/nedegago.pdfIn PDF document text
    • https://tanhoaphat.vn/userfiles/file/63520770016.pdfIn PDF document text
    • http://hkalc.com/userfiles/83722925867.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/9rskl1g8q6h1iql4dd8cecol72/fowejisexesolixijuvuf.pdfIn PDF document text
    • http://ayurvedicclinic.org/userfiles/file/93630257932.pdfIn PDF document text
    • http://koreaseowon.com/ckupload/files/42745081954.pdfIn PDF document text
    • http://thcscatquea.hoaiduc.edu.vn/ckfinder/userfiles/files/30247111727.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/30004323061.pdfIn PDF document text
    • http://intertravel.hu/_user/file/47930564197.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/161484fcf2b824---11531244998.pdfIn PDF document text
    • https://ever-progress.com/upload/files/gimijuzi.pdfIn PDF document text
    • https://doan295doson.vn/namthuan/images/news/files/67959124001.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_off0000bf71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF71 19188 bytes
SHA-256: bf3e2ef776f0428f36f00c3ce74ea9931fd657743f13e3aef04ff54fecde209c
font_01_sfnt_off0000f149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF149 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010960.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10960 10228 bytes
SHA-256: df2872da8ab1aa06ffd3e6b37db18b52261bf6866746e9660c1f17a7cb68c532