Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1def56a0767f3b5…

MALICIOUS

PDF

76.7 KB Created: 2021-09-14 05:48:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e6dd9677ee74cfc7fd9819b6d8731208 SHA-1: 63e9d7fb5c3658c165b0d2fa8cd2e3d056f53d69 SHA-256: f1def56a0767f3b54a0cf7d8a718539d8489f751f13a2f1dcf697a80bf119547
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware distribution lure, likely delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613e021a7e239---6464977628.pdf In PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/9a5b3963bcf9f9df35c89076f020c84e/48901528901.pdfIn PDF document text
    • http://highendschmiede.de/highendfiles/file/45618168649.pdfIn PDF document text
    • http://marymo.ru/uploads/files/bavajabovewat.pdfIn PDF document text
    • http://suamanhinhlcd.net/userfiles/file/68028348470.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/161335d56e4166---bovitekodafapopapufibowe.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/poboxumelutaxumi.pdfIn PDF document text
    • https://sporyolu.com/resimler/files/momimimare.pdfIn PDF document text
    • http://onfireinteriors.com/userfiles/galuzosuramogovufokajikim.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210906075834.pdfIn PDF document text
    • http://energcomb.net/cms_enercomb/sgi_userfiles/userfiles/files/66300036926.pdfIn PDF document text
    • http://zenobiacultura.it/userfiles/file///dejenuvokonomowa.pdfIn PDF document text
    • http://eska-lift.ru/userfiles/file/27656904360.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/b75efc5bcaae3fab47d1efa7266f30c5/62561048504.pdfIn PDF document text
    • http://phubozena.pl/userfiles/file/jetuzinomewomejaw.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/63096496010.pdfIn PDF document text
    • https://araprinter.com/ckfinder/userfiles/files/gubuzuradiga.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/58061704833.pdfIn PDF document text
    • http://kmbb.at/userfiles/file/97764766834.pdfIn PDF document text
    • https://nutritie-metabolism-sanatate.ro/app/webroot/files/userfiles/files/lojomuxoxodibojoj.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/58586744910.pdfIn PDF document text
    • http://inter-travel.hu/_user/file/jeloxowefo.pdfIn PDF document text
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/gejazobubideto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=yify+browser+apkPDF 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_off0000c98c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC98C 17084 bytes
SHA-256: 37b7cb7fdd7a36f986aa5eb04a03b76eab886007c4b4dd76b73ad88ea83bc4d8
font_01_sfnt_off0000f5b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B3 10516 bytes
SHA-256: f56b58749545ddc789fa36ae10e0ed0ada94098cf7d7e78bd9c3c84555b9ee3a
font_02_sfnt_off00010da1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1