Malicious PDF — malware analysis report

Static analysis result for SHA-256 a056f242d37a1598…

MALICIOUS

PDF

91.0 KB Created: 2021-09-01 12:04:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5db075d940fab94534632ff787510c87 SHA-1: 276fcb391652486c3ccbf1e27e28df12741f7d68 SHA-256: a056f242d37a15987ee6afae6544bd93226de35e9434a328b0ee9efbc4edd999
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link T1059.007 JavaScript

The PDF file contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of the embedded links and the PDF structure suggest it's intended to trick users into clicking them, leading to further compromise.

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://synerhu.ru/uplcv?utm_term=cicely+berry+jaw+exercise PDF link annotation
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf997464e6---mafotomidepazuzirorituzes.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210621_18B1555BD68B933C.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1606c84794bc10---81303559947.pdfIn PDF document text
    • https://hssipm.com/wp-content/plugins/super-forms/uploads/php/files/873b15184be0bd9de1b1c79b60f7e7d7/28806562891.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/solajazukijevep.pdfIn PDF document text
    • http://perila-vrn.ru/userfiles/file/14974251830.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/gazuzolodopejotewuxat.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6b7e8234d---lolopabekavekivuzapuse.pdfIn PDF document text
    • http://congtyvima.com/images/Download/74757265404.pdfIn PDF document text
    • http://vencedor.coop/images/admin/file/nipigonamokiw.pdfIn PDF document text
    • http://yavuzselimvakfi.org/resimler/site/files/73149699638.pdfIn PDF document text
    • http://bronia.org/userfiles/file/busuvixiwe.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b2fbd79aabc---zinumuzugujezevaril.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/puzuwowosi.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/aaa67acd94f78ef992b281bd8ae7bf64/funajemutovez.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/17d197de9e2e0c2e7820196afcfb098e/45950731725.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16072947d7cc20---85692934674.pdfIn PDF document text
    • https://inprovitpuertorico.com/ckfinder/userfiles/files/87844709279.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/73638848a92bc3e0e4837e024d222e38/kunaridezefevi.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/5ebf37eb06b9dbfa68c8e4cd328723e5/mimekuko.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a3b9b6ee2---wabagaxe.pdfIn PDF document text
    • https://cevhertemizlik.com/userfiles/files/84096997152.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a6af61032d7---60961772681.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/i3u6lmlsinp5o9vlpbqvnrnh3g/fubusukakazupaxemodeka.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ab786cf56---87090359652.pdfIn PDF document text
    • https://noddy.nu/images/file/titurugurigu.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_off0000fa33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA33 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011245.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11245 19420 bytes
SHA-256: 491da82f63c181b142ff343fded45af70ec6f3d089c87cf401073a10f681781a
font_02_sfnt_off00014463.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14463 10504 bytes
SHA-256: 8b8d26056e3bd2e65d73680c0ed106abf58bda57c0dbf2c1fcc1da19841ea171