Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a1747eec6801e7d…

MALICIOUS

PDF

91.4 KB Created: 2021-09-06 22:13:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 87ddf1b398ad7e0a32a195310be7c48d SHA-1: 134faef90dff706e5446056c86e0120a8de58323 SHA-256: 9a1747eec6801e7d79abefaf53fc8775e95d30c55e0d3e74c1c4f1a604f52ee3
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various domains, many of which are identified as compromised or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or SEO abuse. The document body is heavily obfuscated and does not provide direct textual clues, but the heuristic firings and URL analysis are sufficient to infer a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://www.lukoilmarine.com/ckfinder/userfiles/files/86695643786.pdf In PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/53031188039.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f077d7e32e1---losavijena.pdfIn PDF document text
    • http://agama-rc.com/upload/files/xavemo.pdfIn PDF document text
    • http://buyo-g.net/userfiles/file/22877358870.pdfIn PDF document text
    • http://www.fonfe.com/uploads/files/82758500974.pdfIn PDF document text
    • http://tate79.com/clients/868750/File/wixisarawiju.pdfIn PDF document text
    • http://okulsanmalatya.com/imgup/file/13505308522.pdfIn PDF document text
    • http://etcad.net/np/upfile/file/seditufojar.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/5a3c2287971d8fced9051e1ff77fd507/8957553263.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16103ea55a754c---72183326842.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/userfiles/file/tagukamawike.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/revudopegodojofinofero.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/6fd9ef18771261e92ef373ccab4ae9bb/fogajubibajew.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/63266795542.pdfIn PDF document text
    • https://ckmusicdesign.nl/userfiles/file/22986365868.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/98698353318.pdfIn PDF document text
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/damikemonivotowijatenan.pdfIn PDF document text
    • https://stayatrosetta.com/wp-content/plugins/super-forms/uploads/php/files/p84uicj5c4va19qjfib6mt0uto/47950534431.pdfIn PDF document text
    • https://steammining.com/userfiles/file/fimiletasexeteda.pdfIn PDF document text
    • http://bookblog.kr/data/file//files/10471497323.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=manual+de+tuberculosis+2017+boliviaPDF 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_off0000fa31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA31 11004 bytes
SHA-256: 01b5e845b8084b1338365e2076ea71ae7e6373f1d1af6d55db00d015eed6200d
font_01_sfnt_off000113fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113FA 19840 bytes
SHA-256: b89efee6668c1b26d37cc96a1aebb2fcb5bf88f63c13545e47a0b56ae1cec6e0
font_02_sfnt_off00014808.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14808 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1