Malicious PDF — malware analysis report

Static analysis result for SHA-256 a556cf7505d0727d…

MALICIOUS

PDF

100.6 KB Created: 2021-06-26 16:06:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: b2dbd1a55cb505c687f0dc9b7896b220 SHA-1: 1ba763a827aab54814bb5f069216c0df1c5dc1c0 SHA-256: a556cf7505d0727d17f0da6a41c767e05be8e7cb525f6864ed82353d995317a4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress installations and disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

Heuristics 6

  • 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.
  • 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://a1-recruitment.fr/v2011/Files/fck_upload/file/73045134741.pdf In PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092a19bcd9cf---ludelezo.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160b8204b4bce9---71051209817.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/grmbjikir6itk4prmge7n8mtlj/50656199693.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/75422461342.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d700fe38b3---vejupupegitarusozisotinob.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ede4c24b0---tiwuxipatowelejamabam.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/zemekovatokagiv.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/7mf0d32cucu6m6ai5ul7d7kte3/46651508600.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/35353923359.pdfIn PDF document text
    • http://ingenermarket.ru/userfiles/derozitudodibugosogelofu.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/1623556637.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/t28l0puld2n8200bfrgb58458h/66960058918.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/16071eff757049---18986937993.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085082ce0375---62073165837.pdfIn PDF document text
    • https://vivaldiroberto.com/img/files/mediafiles/file/furipu.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/ciae68o4mta6l62365rqr1t572/68287998557.pdfIn PDF document text
    • http://haiphongcontest.com/images/files/nozux.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/2d7132610d929d3a84a23b061e41ff36/31287649328.pdfIn PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/wanaxeredoluwejegaroxig.pdfIn PDF document text
    • http://www.themixchange.com/userfiles/files/gofasebevuwu.pdfIn PDF document text
    • http://bawwabatrizq.com/userfiles/file/nezulumamipob.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/5454832bcb4dfabc954ba83f0f5a92db/37690209777.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d9aad1b0d---86564557246.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=communication+barriers+pdfPDF 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_off0001268c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1268C 17640 bytes
SHA-256: 05a8c5c3bf07503447a2f3a27c5b3ad5eeef88d28de9a35cb26193df70ac4c45
font_01_sfnt_off000153ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016be5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16BE5 11008 bytes
SHA-256: 68454c540951aa908908c12a2d17b4deb4b5bffc64b91a752a3d8c30307c958d