Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9402091e96f4151…

MALICIOUS

PDF

71.6 KB Created: 2021-09-17 01:59:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 60e904378b1ab0dcdd76072b663d0d7c SHA-1: 46bab795054adf8fec090bc6c46ceeda88cace9e SHA-256: a9402091e96f415149c46274e807d308be66e9b08d037a84e10cc46c4aeb2a5e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure itself appears to be a lure, with the primary goal being to drive traffic to these external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • 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://laborke.ru/uplcv?utm_term=volume+scheduler+android
    • http://yingtailong.com/upload/file/210901123834905258oyx49sfdtkr5.pdf
    • http://masterkontroll.hu/ckfinder/userfiles/files/finijarabugusarafepu.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/32ca1f37c4ef490f79937e2b740d753f/30094431899.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/s48n1u424b2nlc578lltvpubhb/96147928267.pdf
    • https://mi-stores.com/basketballtotaal/images/editor/file/bipazafu.pdf
    • http://bloemenwinkelindex.nl/images/uploads/xutirebuwizamoruwasu.pdf
    • http://evopizza.lt/ckfinder/userfiles/files/fanirevewomerinedozeveme.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/beca366c11988fa9ca3f5c3f46f5f0cf/wogatevudo.pdf
    • http://allier-genealogie.org/File:/jamuzevokubupefamasi.pdf
    • http://keyflounge.nl/userfiles/file/9901385391.pdf
    • http://bluecars.pl/userfiles/file/49663896395.pdf
    • https://qigoodteam.com/uploads/files/202109011254526150.pdf
    • http://adabaskimerkezi.com/upload/file/resenazudetipimafun.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/161340335dd443---95858944444.pdf
    • http://hatowo.com/app/webroot/uploads/files/fotuvinozujukizizikogupev.pdf
    • http://de.ruben.pl/ckfinder/userfiles/files/76878985701.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/d70749d7d00a056dbc0a4ea26fa4bd48/21075606426.pdf
    • https://rowadalbyt.com/userfiles/files/zujapasudaduzewesu.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/161329fc19f7c6---fujozokawidabogoberokuliv.pdf
    • https://lotusmarinevn.com/upload/files/51523856733.pdf
    • http://longruiglass.com/ckfinder/userfiles/files/20210914_121222.pdf
    • https://plentis.eu/ckfinder/userfiles/files/lulegosetibid.pdf
    • http://lnianemarzenie.pl/userfiles/file/bidukememu.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_off0000b80e.bin
b7d52879558e202fa7703433d59166587774832732fb147151a2f2b22558a507
pdf-font-stream PDF embedded font (sfnt) at offset 0xB80E 10608 bytes
font_01_sfnt_off0000d012.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD012 16792 bytes
font_02_sfnt_off0000e824.bin
a0e735a9049db7136244cec8ea3a1ee63d751b75855f5667c74abf3a697933eb
pdf-font-stream PDF embedded font (sfnt) at offset 0xE824 15704 bytes