Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fde165c259df2a6…

MALICIOUS

PDF

84.5 KB Created: 2021-09-10 03:32:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d5bd9566aa1e0550bdc3c1ad6672dc51 SHA-1: b2c96375e3147abf9ada27a6a6c30170111c580c SHA-256: 9fde165c259df2a656a396be654e734064f92dca2dec5926c04395857ce010a9
156 Risk Score

Malware Insights

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

The PDF file 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 websites, some hosted on compromised CMS platforms. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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.idd.no/ckfinder/userfiles/files/77709195979.pdf In PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/88928649177.pdfIn PDF document text
    • http://selidbe-beograd.info/files/48817325817.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/161349b6423984---kaxoripekafixamokujowis.pdfIn PDF document text
    • https://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/rokepazod.pdfIn PDF document text
    • https://ipkameros.lt/userfiles/file/42810355529.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/9810518106.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613350357b098---wepujizolevejosa.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16136565aefab8---badesujezari.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/54445681019.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/87691960804.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/lakamudipitapagikijesevu.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/161390124bf90c---77913242943.pdfIn PDF document text
    • https://meritumptt.pl/dokumenty/file/lofufibovuwalejisixog.pdfIn PDF document text
    • http://paramountswimwear.com/userfiles/files/takib.pdfIn PDF document text
    • http://uptindia.com/newsimages/file///3562167864.pdfIn PDF document text
    • https://jackinthegymtpe.com/uploads/files/202109080416588184.pdfIn PDF document text
    • https://zagi.hr/files/68498439023.pdfIn PDF document text
    • http://abnicum.ru/files/file/zibajovexiwojulisor.pdfIn PDF document text
    • https://h1t-url12shio-turbo.com/contents/files/69513381156.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/benimuvikubalu.pdfIn PDF document text
    • http://tdbakademi.org/userfiles/files/51597145397.pdfIn PDF document text
    • https://artedelvalle.cl/gal/files/file/1141669039.pdfIn PDF document text
    • https://heyratacademy.ir/file/sobodovevuferovubiwupifa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=metal+garage+id+unturnedPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AC 10228 bytes
SHA-256: 971baa23a76cfad806f7317964b0b1d5105f530585d8e7da4500791841c54738
font_02_sfnt_off00010a79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A79 18876 bytes
SHA-256: 3bb11fcf963fa72c7ce2770d7058ecd5616d43887d1a2aaab7a799d107f81b2a
font_03_sfnt_off00013b4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B4B 1964 bytes
SHA-256: cb83427253be486b5dc35224710cea1d2a27078ad6da64da340d8beb93dbb3aa