Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b58b4654ced41e2…

MALICIOUS

PDF

71.8 KB Created: 2021-09-20 22:45:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f2e452277de1218689b05ea9e00d7ffc SHA-1: a3f2da0f4763b5039b182651bedd76164ac2deb7 SHA-256: 4b58b4654ced41e27ea227db26cb5d919ee45e8c8164b1a203a4e1ab092106bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on compromised WordPress sites and disposable domains. The primary purpose appears to be directing users to potentially malicious content, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://crysiq.ru/uplcv?utm_term=vita+app+without+watermark+apk+download
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/b08f2ffea8b1f0cc6b21f10a557749a7/wanaguvilego.pdf
    • http://quangcaosms.org/media/ftp/file/17929338900.pdf
    • https://inprovitperu.com/ckfinder/userfiles/files/kovomanafek.pdf
    • https://360clothing.in/home/www360cl/public_html/uploads/images/files/fitawatuwedum.pdf
    • http://xn--76-6kca8aqc6c.xn--p1ai/pic/userfile/mageb.pdf
    • https://yenicekentkaplicasi.com/userfiles/file/pejebuf.pdf
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/161365d30451c2---subozakipa.pdf
    • http://sake2metustin.com/uploads/files/46717827614.pdf
    • http://directopinion.biz/uploads/FCK_files/file/68829185259.pdf
    • http://divorce-difficile.fr/userfiles/file/64325879418.pdf
    • http://enricobarraco.com/files/94358869965.pdf
    • http://j1medical.com/uploaded/file/xibowanofoxada.pdf
    • http://hstairan.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/1959072399.pdf
    • http://mnarch.it/userfiles/files/mutaxolugivaxavirejofawil.pdf
    • http://quincy.pl/ckfinder/userfiles/files/91428014782.pdf
    • http://tdjl.com/uploadfile/file///2021090502070189.pdf
    • https://nezamirekhaseafoods.com/userfiles/file/88765542682.pdf
    • https://ms02bet.net/contents/files/61260608331.pdf
    • http://ourgans.org/userfiles/files/tetozizazi.pdf
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/sisixexobokogowikupaxapok.pdf
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/35838360471.pdf
    • http://mtcongnghiepxanh.com/upload/fckimagesfile/67186654507.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/8ddc93f57ddf1dc182c9292b1aa14142/60809960788.pdf
    • https://chatham-ebenezer.ckdomain.com/uploads/userfiles/files/40882792308.pdf
    • https://jcmimoveis.com/userfiles/file/wujazav.pdf
    • http://bluecars.pl/userfiles/file/68643566676.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b7ed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7ED 16792 bytes
font_01_sfnt_off0000d004.bin
82110806fd117d0de3948bc1d15aa9e8241e5480faeecc3794df72dd27206214
pdf-font-stream PDF embedded font (sfnt) at offset 0xD004 10736 bytes
font_02_sfnt_off0000e885.bin
238575c60d89b92941caf7722858471e54437443e6f864f1296642f1a1e1da67
pdf-font-stream PDF embedded font (sfnt) at offset 0xE885 16208 bytes