Malicious PDF — malware analysis report

Static analysis result for SHA-256 c99f30079ab1785b…

MALICIOUS

PDF

88.0 KB Created: 2021-09-13 21:27:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8062ea1c664e3ecf4a155c1e4e3e7279 SHA-1: c1e800ddd6a25f5b0de9f3535b8d4645fbadb652 SHA-256: c99f30079ab1785ba6a70acae618cd228854e22d4700c7077559f2e24da4d9a8
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous links pointing to compromised websites, including a WordPress upload path, suggesting it's part of a link farm designed to redirect users. The presence of external URIs and a link farm on disposable hosting indicates a likely attempt to distribute malicious content or phish credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/d3de92784edf5c486a94f29d2ac5aec9/84000747442.pdf In PDF document text
    • http://thanhnienxp.com/vietkiendo/upload/file/safunivipofuwuf.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/vonepidigapedadanojodexag.pdfIn PDF document text
    • https://congtydaihai.com/upload/files/sitevo.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/37561312325.pdfIn PDF document text
    • https://apsco.ly/userfiles/files/tenavugununonu.pdfIn PDF document text
    • https://mmtours.si/uploads/dorixizozodoveliliko.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210906154804.pdfIn PDF document text
    • http://gccde.com/downloads/blog/geust/files/tevotowinub.pdfIn PDF document text
    • http://dzbnf.com/upload/file///tulosugug.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130999e395bb---tafijumaxokikamexifupob.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/11093760345.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/93b0fd3805c39ca6cd7435af08fe7fbc/90005919599.pdfIn PDF document text
    • https://skvely-kup.cz/files/file/8378226205.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/96929690591.pdfIn PDF document text
    • https://ruedi-leuthold.com/userfiles/files/68980544218.pdfIn PDF document text
    • http://www.ujepites.hu/userfiles/files/88856388954.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/bifosima.pdfIn PDF document text
    • https://ijtm.in/userfiles/file/muwodutipibuzogutitim.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/58730885299.pdfIn PDF document text
    • http://groupementpecheduloir.com/ckfinder/userfiles/files/16199500823.pdfIn PDF document text
    • http://agrion.org/upload/fichier/22329322630.pdfIn PDF document text
    • http://canphantich.net/Images_upload/files/73420087860.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/sovaporozukulovum.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/a7f11368d21389e88c572dcfa65845eb/vupowiruvafonaba.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=shooting+games+for+ipadPDF 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_off0000f3e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3E4 17332 bytes
SHA-256: 983c20a12687b13c75783cbe69b368e5b0ba8d678838a4c8b992e055d5c87495
font_01_sfnt_off000120f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001390a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1390A 10972 bytes
SHA-256: 06746b23c19731107c665560d5db4d3b97dcbeddbff5d9774458219d10a26f03