Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb389f152dc2d921…

MALICIOUS

PDF

75.1 KB Created: 2021-09-20 07:15:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f8f08f729accbd8f75454ec0596b3d6a SHA-1: 7763eb46f5912f581ed7c84e5f97b9a27bf35685 SHA-256: fb389f152dc2d921770273c31c47b3081d17ad72e726e0fed129caf66c0c5ebe
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs, many of which point to disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically phishing. While no scripts were directly extracted, the PDF structure and embedded links are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://odpadykj.cz/UserFiles/File/29595806639.pdf In PDF document text
    • http://abnicum.ru/files/file/74350827121.pdfIn PDF document text
    • http://banghetretruc.com/media/ftp/file/84019734586.pdfIn PDF document text
    • http://teplospectr.ru/images/files/34325805746.pdfIn PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/46697954000.pdfIn PDF document text
    • http://yamamatoen-wanwan.jp/ckfinder/userfiles/files/8345653448.pdfIn PDF document text
    • https://austarpharma.austarchina.com/upload/files/gerimiweremasujeku.pdfIn PDF document text
    • http://jimsclub.net/new/board/img_tinfo/file/20210917230108.pdfIn PDF document text
    • https://brillimet.com/uploads/files/202109120153178832.pdfIn PDF document text
    • https://novinfasteners.com/userfiles/file/79088301889.pdfIn PDF document text
    • http://sitarofindiamd.com/userfiles/file/pupedilejalabopelemefo.pdfIn PDF document text
    • http://xn-----6kcaheblih5ab0a6afqbzoqe.xn--p1ai/ckfinder/userfiles/files/70160482329.pdfIn PDF document text
    • http://xn--h49al71atridzo.com/userData/board/file/wimuzulaxeb.pdfIn PDF document text
    • https://navoloki.mebel18.com/uploads/files/binigoxipa.pdfIn PDF document text
    • http://skonasystems.com/userfiles/file/zepidarovonezavabusafepe.pdfIn PDF document text
    • https://gbp.dropship-online.com/userfiles/files/jujepidiwivekawixerasup.pdfIn PDF document text
    • https://bedandbreakfastchia.it/userfiles/file/25712907402.pdfIn PDF document text
    • http://gpkoaee.ru/ckfinder/userfiles/files/bumigotugozubutonosapud.pdfIn PDF document text
    • https://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/15329972156.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/bujov.pdfIn PDF document text
    • http://geombiagioschettino.eu/userfiles/files/14520759344.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614013f6ac0f8---54019955557.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140f7bcac7be---17353385778.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+restore+icloud+passwordPDF 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_off0000c098.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC098 10580 bytes
SHA-256: 4de7fd8a9eec0f1df9b4a3dc06b238365a33493a1c2408ed45e17817d109f90d
font_01_sfnt_off0000d8ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0FE 17604 bytes
SHA-256: bb347bacc811cc0b9565d39f788b23b5e28b88c13da2230d1fc72bae8586cc44