Malicious PDF — malware analysis report

Static analysis result for SHA-256 491dd38fb51ab5fe…

MALICIOUS

PDF

94.7 KB Created: 2021-08-13 13:44:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b4ec53663ec331e0ea98e87df50afd94 SHA-1: f9bf6a2083eb7bb514fd82fdcaa35e96b2470af0 SHA-256: 491dd38fb51ab5feb5db0ec566836d7ea42653e792c83b47c5e90aaee024557e
164 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple domains, many of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading a secondary payload. The presence of a 'download button' heuristic further supports this phishing-like lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://al-farh-iq.com/upload/userfiles/file/20643122477.pdf In PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a054842a0a---nalasigasikuza.pdfIn PDF document text
    • http://hornets88.com/clients/56662/File/67051845809.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021050819121760.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/lalodogutawujedaxufa.pdfIn PDF document text
    • http://postelezmasivu-brno.com/ckfinder/userfiles/files/13725077941.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16099f09cc1153---18489304587.pdfIn PDF document text
    • https://uleshuzatabc.hu/files/file/16706760178.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/99910359559.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085242bc3bdf---53767184801.pdfIn PDF document text
    • https://ehbo-oostkapelle.nl/userfiles/file/28354800438.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/meliwidozi.pdfIn PDF document text
    • http://tropo-design.com/ckfinder/userfiles/files/duxibubezo.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/notakugodorotelagabumusu.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/b1548320d37c7fedeaad2051ec038549/xezisogutazol.pdfIn PDF document text
    • http://ncteonline.com/userfiles/file/gosabid.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/bafddbc576f7c8378c9f49e1a2002b91/38363390032.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/84ca1b6e40d6d1467fb19d99bcba2386/77133303326.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/dotavuzobulirilaji.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbd5f18e3ab---71518835369.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609afb40a72d2---turipububusedazidefibem.pdfIn PDF document text
    • http://transfertrolley.cn/d/files/josumilurabok.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/1578fcac90420ec8ad61cfd509f560c5/41269835169.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/wemozisidiwupi.pdfIn PDF document text
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/d2a537010d8931af77c41dfcbf9cd43b/40800171806.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=can+i+get+garageband+on+windows+10PDF link annotation
    • 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_off00010f85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012797.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12797 16960 bytes
SHA-256: 921305f2ca96716a396647b0be086fd96bdd04ca968a872a33b2e11f13d5c289
font_02_sfnt_off000153e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153E8 10808 bytes
SHA-256: 23c6b37f096e0c7dd19f1b2fa2ad95c3f708f9db1e1800b3f74ab3895c70bf91