Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dc1416a158e666b…

MALICIOUS

PDF

87.7 KB Created: 2021-07-01 14:02:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: e5b9d468b9582690029949502f8f778a SHA-1: c99a3b0c5ab97723061fe413c273a6e8b4e78221 SHA-256: 4dc1416a158e666b86d685bb976bfffdaf5683a545f64189484153c5e35c39ea
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to potentially compromised CMS uploads and disposable hosting. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of many external links suggests a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/3a55576c227875e46a2b9a0eb585d612/22251199176.pdf In PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/7ebe77edff8f1046829352613fce98d2/95370629978.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ccbd0483da---13991141137.pdfIn PDF document text
    • http://minerva-collection.net/files/files/69353118144.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/wuzidoxugoluwejegojikuxi.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/lanenik.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944d3ec337d---gamelajulobixup.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/lowapu.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160923b7617cc8---revan.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609f0ecc6fa30---40811164268.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/tg9c24cvupmdkadvitjnde0si5/38659538632.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cb0d5333c83---83835807388.pdfIn PDF document text
    • https://eternalbliss.net/file/dixinoronukelev.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7e1a9d25b---josimuriwivu.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e4b067a1c3---rinagetoteselusoludara.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/11416463588.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/43767839020.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099bb8ba511e---42103301167.pdfIn PDF document text
    • https://marosme.ro/hirek/file/zakibebeditowatunefata.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/90213677501.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c188036367---15381800682.pdfIn PDF document text
    • http://royalrep.com/userfiles/files/fupiti.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/73276105230.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/o8b0mhij15j4lc18g69ne7grs8/jimakevunomigiwamiwuj.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/ldmk616ur6tiqdo5duh4ngei6f/12059869491.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=gvk+power+share+pricePDF 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_off0000f402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF402 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C14 17524 bytes
SHA-256: d45b3457e1712cd5a25b67f24418027ca0a8f7cf20644ee63b83f0a8e4957b29
font_02_sfnt_off00013a5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A5A 10504 bytes
SHA-256: 1a3ab7821b3cdec293f49fa24bbb5c691149fece974e7737c15ab93682285746