Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5f8b355f44abd68…

MALICIOUS

PDF

80.3 KB Created: 2021-09-16 23:50:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b26ca22c016ada218c5552ed5f6112e7 SHA-1: c9fdd373e936b62f1cfdbfee97084b11b3c19b1a SHA-256: d5f8b355f44abd68e235ab26836e6c471c56bf7b6043875b1fa39f93f58bcf32
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous external URIs and is structured as a link farm, with many distinct hosts each pointing to a single PDF file. The presence of multiple external URLs suggests an attempt to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • 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.
  • 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://infrive.ru/uplcv?utm_term=cast+android+screen+to+pc+windows+10 PDF link annotation
    • http://geotersrl.it/file/tadefolenugemavufoperisi.pdfIn PDF document text
    • http://annassteen.com/ckfinder/userfiles/files/9161271667.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/57196563293.pdfIn PDF document text
    • https://dwitunggaljaya.com/sitefiles/file/padapunoverazepoxelefom.pdfIn PDF document text
    • https://lorus.rs/files/dubagekemilas.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/vomopota.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/tesamimefafunuromowop.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b2a9d0699---70341679979.pdfIn PDF document text
    • http://katachizu.com/img/news/files/52722535959.pdfIn PDF document text
    • http://alltimescare.com/attachment/files/86031199822.pdfIn PDF document text
    • http://xn--12cfu9bc1efac9a9azfdsb7b9d1f0j.net/ckfinder/userfiles/files/xuwodowetet.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/xorixanupakeraxege.pdfIn PDF document text
    • http://grafitym.kz/files/file/85988432573.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210902082228.pdfIn PDF document text
    • https://jsptti.com/ckeditor/ckfinder/userfiles/files/76232915803.pdfIn PDF document text
    • http://licausi.it/userfiles/files/3863327652.pdfIn PDF document text
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/jobutaxeti.pdfIn PDF document text
    • http://studiocariola.com/userfiles/files/fegasiriwuvek.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/99549448088.pdfIn PDF document text
    • http://automozg.by/upload/editor/files/xakotugagevewevux.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/3da80e4bad30f38d61dc2712adf58686/vomirolunanat.pdfIn PDF document text
    • https://eliteplacementagency.com/uploads/files/xufopatojezewiser.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/livawipejugosot.pdfIn PDF document text
    • http://sunway.me/uploads/file/1010251569.pdfIn PDF document text
    • http://skolky.info/foto/images/file/sudurajeburujiwof.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_off0000d51c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD51C 10752 bytes
SHA-256: eec9cb9fb1e8b17dfeb338502f958ea798a7b8e99a3a575041e8cfcf91e8aafd
font_01_sfnt_off0000ee15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10627 17704 bytes
SHA-256: 1b7ffce27e5c9cf5545f2dcf1dd556ca61ea1e055cbaf0f4886e594febe438bf