Malicious PDF — malware analysis report

Static analysis result for SHA-256 f05c8b833119ae0e…

MALICIOUS

PDF

76.0 KB Created: 2021-09-14 05:11:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 08a0c24bad7303b2a225ecb791f40a34 SHA-1: 78a76796b90b97f0bde5d82bdefebbb24b9ab003 SHA-256: f05c8b833119ae0e07dbbc0cd9cc1ed43f947a2b0f5cec273d2c2ead198d0612
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Multiple URLs extracted from the document point to potentially compromised or disposable hosting, suggesting an attempt to redirect users to malicious sites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL analysis strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://dotacjedlaoze.pl/userfiles/file/dagoveda.pdf In PDF document text
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/xixuku.pdfIn PDF document text
    • https://samsunyapi.com/userfiles/files/22641456109.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/rovugibetejasolokales.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/babipetu.pdfIn PDF document text
    • http://igruppe.no/ckfinder/userfiles/files/mubizuleludari.pdfIn PDF document text
    • http://mybyblos.com/userfiles/file/33322922253.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/xanenolofisupezipaso.pdfIn PDF document text
    • http://florylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zalufetumevuribipuni.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613baa97afb5c---gevefi.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/zozakiwexenipep.pdfIn PDF document text
    • http://aptekarynek.pl/zdjecia/fck/file/xigemijimojagipelapimuxik.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613fef680123c---27958832481.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/dofidamukujikowuki.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/34243980869.pdfIn PDF document text
    • https://mashtalkandil.com/userfiles/file/66158364769.pdfIn PDF document text
    • https://safrano.pl/userfiles/file/gusabudovuvokawiti.pdfIn PDF document text
    • http://purplebyanki-com.bvirani.com/ckfinder/userfiles/files/niwepaw.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/73660642282.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613decd104d34---lelajemeviwimu.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/notuwalasimobosikaxolun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=opposite+words+in+english+a+to+zPDF 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_off0000c5e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5E4 10844 bytes
SHA-256: 9ef3c0d3bbcb31ef64c54725dc3bd6791cd499feb9810511f4d139e5f1f5fb50
font_01_sfnt_off0000debb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEBB 16924 bytes
SHA-256: 2edfb51dae07b15f27eaf3c1c0be6ac2673d01a9b3ce35330724df0c4ebb43d9
font_02_sfnt_off00010a62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1