Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa72ef4c92564cec…

MALICIOUS

PDF

68.4 KB Created: 2021-09-28 20:13:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2f1d630b337eaf0f9b189b020b98d4fe SHA-1: 4734e66483dca7db9b27f4c2908f09579d718c1b SHA-256: fa72ef4c92564cec869dc678c1f1e6b9ed5ebfc6c6af8ec7fd37387444be5ab3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous external URIs and embedded URLs pointing to disposable hosting, indicative of a link farm designed to redirect users to malicious sites. The presence of PDF-specific heuristics like PDF_SEO_DISPOSABLE_LINK_FARM further supports the phishing lure attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://nomylo.ru/uplcv?utm_term=time+travel+app+android PDF link annotation
    • https://magicdiscoradio.com/userfiles/file/40129415840.pdfIn PDF document text
    • http://sea-cruise.ru/ckfinder/userfiles/files/bakojiwitazaxi.pdfIn PDF document text
    • https://viboot.com/ckfinder/userfiles/files/folojefolidofavosatowi.pdfIn PDF document text
    • http://www.guus.edu.mn/ckfinder/userfiles/files/golinop.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/59829146474.pdfIn PDF document text
    • http://conflictfreeelectronics.com/ourprojects/chowki/UserFiles/renuka/file/39754799344.pdfIn PDF document text
    • http://inarchengineering.it/userfiles/files/40017187520.pdfIn PDF document text
    • http://salwex.hu/file/33058696453.pdfIn PDF document text
    • https://bostaninsaat.com/image/files/pefaxadi.pdfIn PDF document text
    • http://naasschoolofmotoring.com/fckeditor/userfiles/file/75508865822.pdfIn PDF document text
    • http://flynewsletter.com/uploads/file/95363603774.pdfIn PDF document text
    • https://toskov-yordanov.com/userfiles/file/jogowutisen.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16141c2be32c1e---zesapesixilasevezuka.pdfIn PDF document text
    • http://pevak.info/UserFiles/File/dovigetifafifovuludubaba.pdfIn PDF document text
    • http://tg-focus.ru/userfiles/files/sifisozapuvigadetoji.pdfIn PDF document text
    • http://babamoleskine.com/files/file/18789820123.pdfIn PDF document text
    • https://fptica.ru/images/file/suvasijefiza.pdfIn PDF document text
    • http://aromaonly1.com/yamituki-n/uploads/files/tukajuvevumetudebulunu.pdfIn PDF document text
    • https://soroptimist.be/oldsite/intranet/ckeditor/ckfinder/userfiles/images/files/45877586974.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/bc0859f5d96efdb9657a862750a0dec1/48089067076.pdfIn PDF document text
    • http://temdientu.vn/images/ckeditor/files/lanofiwarowunasetipilafor.pdfIn PDF document text
    • http://www.agenbenangbandung.net/file/pezavovux.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/25155510327.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/xutedosapopatidenatifirat.pdfIn PDF document text
    • https://www.huaikrachaohospital.go.th/assets/global/lib/ckfinder/userfiles/files/58018781714.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_off0000afb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB1 14672 bytes
SHA-256: 876fc2af5998ff06ae71658369a3dd0a28ca2f80eeb313ee4ecf85a39623b302
font_01_sfnt_off0000d47b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD47B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC92 10412 bytes
SHA-256: a9ccea79417b5490e9caf67bc30d5e2e4dff12dadcac4693db38c0e06231d334