Malicious PDF — malware analysis report

Static analysis result for SHA-256 923cb8fc130e0941…

MALICIOUS

PDF

91.9 KB Created: 2021-08-09 12:02:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 29576c01dda42f8daef184958ace1aca SHA-1: 365ffaa348f7a962cca4498c73a5f39d238a18de SHA-256: 923cb8fc130e09413ec0724daa9e2c2c01bd4c56392c7e2f7987d29572152c3f
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and does not provide clear instructions, but the presence of multiple external links is the primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://parmalab.it/userfiles/files/34639145792.pdf In PDF document text
    • https://balajihighfields.in/userfiles/file/32370363360.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f03d6a8ec24---46325822396.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/fc5c76e827122585001f66f0779494dc/navipazama.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160cd7e1c98f5d---2371796724.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607260f5bcb54---98316645102.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/a3a42fbf89e7c1157f7f973dcff16845/53531810271.pdfIn PDF document text
    • http://iuoooo.com/filespath/files/20210802110604.pdfIn PDF document text
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/3607ff871b74441da91fdc4e8353e55c/26205544106.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/xuwamuzaget.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/fariwatasimigewiteloto.pdfIn PDF document text
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/zemenufexisipukuboboxipu.pdfIn PDF document text
    • https://papiratisk.cz/soubory/merurinejewolavobe.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160842f2d0ee20---4795061442.pdfIn PDF document text
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609afb40a72d2---turipububusedazidefibem.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/1095213425.pdfIn PDF document text
    • http://studiopol.com/userfiles/files/fipidulelu.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b39fde7098f---24547501059.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/sodofebe.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/fazisadigupuxi.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/56620881118.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a1a346b10---lizolu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad2cdaae6f---58491699279.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160793a49635b8---29609812794.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c74184c3481---23049075176.pdfIn PDF document text
    • http://aexpress.lv/index/images/up/file/90980634850.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=call+of+duty+black+ops+2+cheats+pc+single+playerPDF 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_off000101fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101FB 11496 bytes
SHA-256: 4c4b242c206c65b361356a93097ecd199a46fe1494181fd3e8de407485299bf0
font_01_sfnt_off00011cd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CD5 16832 bytes
SHA-256: fdf1baa34a0b6f898ad387c41bfd8c67df30b36b99edfab8a48d4e177db35b71
font_02_sfnt_off000148d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1