Malicious PDF — malware analysis report

Static analysis result for SHA-256 e73a6267dc2a9ee1…

MALICIOUS

PDF

90.4 KB Created: 2021-10-10 13:55:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a6537e319a191fb183f880472b01f526 SHA-1: 682c014f8818af575ba7ff5a0e2e9c98b5e2e592 SHA-256: e73a6267dc2a9ee16e1f2e700249ae87dfc2512b0b11a28005d58141888fa80d
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and ML classifiers indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of numerous URLs, many associated with SEO-poisoned content or compromised CMS uploads, reinforces the phishing and redirection attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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://crysiq.ru/uplcv?utm_term=how+to+convert+from+heic+to+pdf PDF link annotation
    • http://lammensfilip.be/uploads/files/20059789873.pdfIn PDF document text
    • https://businesslife.com/content/files/92246802197.pdfIn PDF document text
    • https://flour.co.uk/ckfinder/userfiles/files/tumawuvisirasizexoti.pdfIn PDF document text
    • http://rpelektromont.cz/admin/obrazky/file/79411861365.pdfIn PDF document text
    • http://deforma.it/userfiles/files/maxijonogokafinuxuk.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/wesirumakezowaguvati.pdfIn PDF document text
    • http://travelsi.ru/ckfinder/userfiles/files/vuximomowujapexujoma.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16153ac2ccc361---35632986744.pdfIn PDF document text
    • https://hotelgaric.com/upload/datoteke/28014895538.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/bffbdce8f17a3064a2515a5ecb4cb6ee/65855840510.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/relakividiga.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/sulafelazej.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109080610386456.pdfIn PDF document text
    • http://gonzagafood.com/userfiles/files/61441999181.pdfIn PDF document text
    • https://xn--dokumaanahtarlk-llc.net/userfiles/file/tikovatexasuji.pdfIn PDF document text
    • http://darstin.com/userfiles/files/jedufipuviropo.pdfIn PDF document text
    • http://www.como-grup.ro/fisiere/file/safovosuvukupezasur.pdfIn PDF document text
    • https://adverto.ee/userfiles/file/66058389234.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1615073e4df61d---7855222063.pdfIn PDF document text
    • https://www.wroclawmodelshow.pl/ckfinder/userfiles/files/73139622543.pdfIn PDF document text
    • https://krygina40.ru/UserFiles/File/16509548758.pdfIn PDF document text
    • https://ceccardolj.ro/userfiles/file/kizulikafaf.pdfIn PDF document text
    • http://hzxgdz.com/images/upload/File/66524401573.pdfIn PDF document text
    • https://minhgianggroup.vn/upload/files/sazogimok.pdfIn PDF document text
    • https://t2sc.me/userfiles/nasibetanuj.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///2021100733423_726250651.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_off0000f661.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF661 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010e73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E73 21140 bytes
SHA-256: 0d46b58be3ca794817b22cf6ad7fc53082037c83d83b62ba6fda928740b0214c
font_02_sfnt_off00014365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14365 10652 bytes
SHA-256: bba4475a2ac74c9acfefa46d863599aba2f2104f8773759d3995ee23e5df2b09