Malicious PDF — malware analysis report

Static analysis result for SHA-256 3281faa068d68d93…

MALICIOUS

PDF

81.7 KB Created: 2021-09-16 06:47:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c63102f9ef7f95494fc8d7dadda2deaf SHA-1: 7652c9164d19da6e3b977320584140b3a40e1607 SHA-256: 3281faa068d68d9398be4eb657ba6003c73e80395ff4eb28f111e006ea9f02cc
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, many hosted on compromised or disposable domains. The embedded URLs and the PDF structure suggest an attempt to trick users into visiting malicious sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c2d3d15db3---12979515566.pdf In PDF document text
    • https://247christianity.org/fckeditor/userfiles/file/807501524481630710556.pdfIn PDF document text
    • http://business-plan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/57762560572.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c719967652---15561864924.pdfIn PDF document text
    • http://clickvay.com/upload/files/jotawefukarivinede.pdfIn PDF document text
    • http://nadafashionbelt.com/Uploads/file/wiladako.pdfIn PDF document text
    • http://asja-doll.ru/userfiles/file/xozudebi.pdfIn PDF document text
    • http://thueotodn.com/uploads/image/files/38609848961.pdfIn PDF document text
    • http://membranekeyboard.pl/_data/file/larapozeluburupusejozo.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/nirewawefotidonomu.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/48832706385.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/91057714140.pdfIn PDF document text
    • https://actsonics.com/uploads/files/202109041608093186.pdfIn PDF document text
    • https://pinkrali.com/calisma2/files/uploads/91238920325.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/80045077905.pdfIn PDF document text
    • http://hani-bee.com/userfiles/files/zodiwomupuwogete.pdfIn PDF document text
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/vuxiki.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/0rlhd3158ii9sqrnvom79ivl3e/58653943498.pdfIn PDF document text
    • https://abctranslink.com/ckfinder/userfiles/files/45881809085.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/navagesaputunovuse.pdfIn PDF document text
    • http://www.toptehnik.si/images/rewibefaneji.pdfIn PDF document text
    • http://tele-klass.ru/i/upload/files/89522619600.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3861c039faae492fdef9ec9577e0e935/29792382010.pdfIn PDF document text
    • http://geredekombiservisi.com/userfiles/file/78927773870.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=android+tethering+applicationsPDF 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_off0000db29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f340.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF340 10772 bytes
SHA-256: 6ba4779d84e7b0c213561590f1e6ccc096aa38177c607f659993c42303ae9c52
font_02_sfnt_off00010bc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BC5 17268 bytes
SHA-256: 1217f3e551129fb23c3d7ed6ecc6bfdd45aa9836213f5af984ce9be6e5b56f30