Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4cfeb51e54a142a…

MALICIOUS

PDF

81.5 KB Created: 2021-09-03 10:52:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e592d14ef5fa18e5c4872689e6bcb7e3 SHA-1: 188067eb2216dec765fb9a1314d62f7474b99444 SHA-256: a4cfeb51e54a142ada35240c12ccf31e1c701de14c5c5296623d4ed184832773
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to numerous external URLs, many hosted on compromised CMS platforms or disposable domains, suggesting an attempt to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://accuratesearch.com/userfiles/file/rasizajotufajegike.pdf In PDF document text
    • http://busangh.com/attfile/fckimg/file///20210602212618_999776256.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/8qf6jbqb23gt9gbqf78ncnqc0t/tulagorimejutogu.pdfIn PDF document text
    • http://schule.havonix.com/ckfinder/userfiles/files/menovefemen.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/zomalozurod.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/qf81dg0e08cv4cn5g4tfag43p4/58072545556.pdfIn PDF document text
    • https://afayl.com/userfiles/file/53595051509.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/7f447bd4a1ccee1857c5a60649fa6978/67114374269.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/97915371311.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/53580466704.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/72162812238.pdfIn PDF document text
    • https://kede.org/userfiles/file/tojuwejix.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/75426172351.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ecbfb1993---56030133251.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d383b3da92a---60471381658.pdfIn PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/j2n5a8nou3k85fu3nii6g1cvv3/23514583627.pdfIn PDF document text
    • https://nmg.lv/img/uploads/files/bosabug.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/1e11b4ea743545dc0af4f6f4d619e604/40378423989.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b70c163f067---fabaferos.pdfIn PDF document text
    • http://gintaras.cz/userfiles/file/demofumuligakitu.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/nn4drlriv98ho5p554fpef78oe/67600003821.pdfIn PDF document text
    • http://droneducational.com/admin/userfiles/file/nekovixujitewarimuxiviroz.pdfIn PDF document text
    • http://canvangdientu.com/images/file/32566595730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=portfolio+design+pdf+downloadPDF link annotation
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/ecb334de734371387a641233a6d42b69/lugitigis.pdfIn PDF document text
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/705ba472b73ba1a0708c109db8d96f15/37068482602.pdfIn PDF document text
    • 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_off0000deee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEEE 15772 bytes
SHA-256: dab7d859f6c66c3a5bdcc8095d3294efe22ae43b5858fe301d5537fba06253f2
font_01_sfnt_off00010762.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10762 10760 bytes
SHA-256: 87d390cabc537a167a32d7035b081806913617b158c72d7241560142251ec552
font_02_sfnt_off0001201b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1201B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1