Malicious PDF — malware analysis report

Static analysis result for SHA-256 635142d2c192aa8b…

MALICIOUS

PDF

83.5 KB Created: 2021-09-12 16:13:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: bad5e654d4299a94dad1c83914c7edbb SHA-1: 421fdff136b90c3328c8597799e96f2f8d61e97a SHA-256: 635142d2c192aa8bd1e851c29594b826fb2b451eb41a1f10bf8a393e66cc8a91
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also hosts a large number of external URIs, many of which appear to be link farms, suggesting an intent to redirect users to potentially malicious websites. ClamAV and ML classifiers strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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.
  • 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=programma+per+scaricare+giochi+per+android PDF link annotation
    • https://horgaszvelem.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/33795418759.pdfIn PDF document text
    • http://hichipper.com/hichipper/uploadfile/file/2021090114533873499.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210904_105850.pdfIn PDF document text
    • https://szalkasszorutacskok.hu/app/webroot/files/content/files/26452446840.pdfIn PDF document text
    • http://vxclouds.com/userfiles/file/remusorizofekizuxomo.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-7/20210907072845152197.pdfIn PDF document text
    • http://mispuntossaga.com/campannas/file/dilif.pdfIn PDF document text
    • http://deauville.ru/files/file/52197360024.pdfIn PDF document text
    • http://gioiacompany.net/images/upload/file/wufiguwezafikopep.pdfIn PDF document text
    • https://semangkamerah.com/contents/files/vefodesomawopijaw.pdfIn PDF document text
    • http://yuli-china.ru/d/files/denetepokumatiwe.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/47522ea20c69492a4bea674af5339fb7/xituliro.pdfIn PDF document text
    • http://mobilni-kadernictvi.cz/files/file/86289393872.pdfIn PDF document text
    • https://sherwoodchamber.org/ckfinder/userfiles/files/89078523546.pdfIn PDF document text
    • http://tanabuauto.com/js/upload/files/4840892880.pdfIn PDF document text
    • http://scuderia512.com/js/upload/files/25421392096.pdfIn PDF document text
    • http://fullx.net/files/46240455230.pdfIn PDF document text
    • http://dongduong.net/Images_upload/files/gujerofa.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/11639671754.pdfIn PDF document text
    • http://www.lbtfilm.com/uploads/files/majalov.pdfIn PDF document text
    • http://ardennes.proximeo.com/ckfinder/userfiles/files/salorijekavero.pdfIn PDF document text
    • http://www.gpkoaee.ru/ckfinder/userfiles/files/24708890416.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/nusamibenisewawedatukod.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210909185934.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/92088968225.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210907_05045928FE05E054.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_off0000e1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E3 17260 bytes
SHA-256: 143403d8707ce8426f23ba4541189a179d1d10272c1b6eebd1455957903fce17
font_02_sfnt_off0001270a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1270A 10820 bytes
SHA-256: dda8f2d4651cb92a755fa24c788c1ceeebd9f5b88f9133ecfe208acfc745ee50