Malicious PDF — malware analysis report

Static analysis result for SHA-256 4609bae4a857ca1e…

MALICIOUS

PDF

77.2 KB Created: 2021-09-06 20:50:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9f3003e941b43e426e575f6904de5f8a SHA-1: 28a539d433f7c699cee062e566a69e582e3bda1b SHA-256: 4609bae4a857ca1e41e658a0dfe687472c4c64ef521ba8c2073a6b06fe48e173
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised or disposable hosting sites, likely for phishing or SEO-based malicious redirection. No scripts were extracted, and the document body was unreadable binary data, suggesting the malicious functionality is embedded within the PDF structure itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/j0abcb53sekto5166rsmklgd22/89021716727.pdf In PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff27b18049---puniponamoxujiso.pdfIn PDF document text
    • http://ladyqueen.it/userfiles/files/66496152310.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16090b75f40cd1---befaxutasidopumadufokik.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210514215833981546nn4tor.pdfIn PDF document text
    • http://wheatland1971.com/clients/25033/File/31599360066.pdfIn PDF document text
    • https://ajitcoatings.com/uploads/86440005790.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607f55ae7756e---gipedijemeluzukonutakipod.pdfIn PDF document text
    • http://erex.hu/upload/file/51841002277.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/latuwadinemorelusifi.pdfIn PDF document text
    • http://svsteinfurth.de/radsportfiles/file/paxelifezav.pdfIn PDF document text
    • http://7seapharmtech.com/Uploadfiles/files/74304314023.pdfIn PDF document text
    • http://accapierre.it/userfiles/files/66473414577.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/bef5aafb85c9da8aff508e5024759d67/30426179072.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/41500089853.pdfIn PDF document text
    • https://www.assofmt.org/ckfinder/userfiles/files/kegilologu.pdfIn PDF document text
    • https://doxity.ro/ckfinder/userfiles/files/tevin.pdfIn PDF document text
    • https://history.tlshaa.org.tw/ckfinder/userfiles/files/87241068535.pdfIn PDF document text
    • http://gdfsztal.com//uploadfile/files/52199660773.pdfIn PDF document text
    • http://sillajen.com/fckeditor/_upload/file/57210542052.pdfIn PDF document text
    • http://i-dron.cz/data/file/55135306874.pdfIn PDF document text
    • https://fcksa.com/ckfinder/userfiles/files/visefofugusezer.pdfIn PDF document text
    • http://escrima-rlp.de/userfiles/file/pufusifiwasuwasimigafepe.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/lepijabefepa.pdfIn PDF document text
    • http://dj-maily.com/uploads/pages/files/39625371976.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1dc13bc5f2---dusesiwa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=accident+and+emergency+radiology+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_off0000c7fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7FE 10892 bytes
SHA-256: 7ceb3ff57df0ccae0b3829571d5ebb65c9a37b902c00450e6543e7d6e75a68a3
font_01_sfnt_off0000e0f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f90b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF90B 17736 bytes
SHA-256: 799c7ba94852bd46322350ddd14eb9e4fcc811c6caae0278493330195950e183