Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a434e3b4a3b54f8…

MALICIOUS

PDF

86.5 KB Created: 2021-09-22 09:13:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 80c92d4d3872f06dda9731a3b726663b SHA-1: feb6a91e192d4dd5eaf3397339ca67660147af4b SHA-256: 3a434e3b4a3b54f89fc5156f00098c5023dcea410f25268c470053c579204861
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised CMS upload storage and disposable hosting, likely to distribute further malicious content or phish users. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://sluchatka-shop.cz/files/upload/files/pazoruzoregowisik.pdf In PDF document text
    • https://gretajensen.com/ckfinder/userfiles/files/takadozadotirigitiz.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16137a7881e22b---gukewukulotigiwa.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/b3ab4f8c80e68f522347fc386d1e20f5/xudajinunibugawokaxo.pdfIn PDF document text
    • https://carmelocuritiba.com.br/ckfinder/userfiles/files/57394084874.pdfIn PDF document text
    • http://digilit.ir/basefile/digilitir/files/26116829686.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161463b2fe2b62---51842876073.pdfIn PDF document text
    • https://khabul.mn/mmpa/userfiles/files/94219695894.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/10161907959.pdfIn PDF document text
    • http://medrea.ru/upload/files/60738026793.pdfIn PDF document text
    • http://lamelove-zakryti.cz/userfiles/file/bodikunijijozuxekedubawu.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/9adaeb70f5c271effa229f518bc21732/jimizesuguni.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141d62a44beb---7815391083.pdfIn PDF document text
    • https://ekoelprom.pl/public/images/editor/file/gijevitepogazegemoxa.pdfIn PDF document text
    • https://giaiphapthietke.vn/media/file/files/fojejozudidimopul.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/xemasitoja.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/22933c5c320e5f5b25032cd03fde585c/65383489941.pdfIn PDF document text
    • http://drumlockingclamp.com/FCK_Editor_Images/files/redofog.pdfIn PDF document text
    • http://bonezi.morefriendship.com/upload/files/62889427152.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/fogozilipomifiwifobekan.pdfIn PDF document text
    • http://gro-felix.si/uploads/pulisedetofidodovumosug.pdfIn PDF document text
    • https://tpijobportal.com/ckeditor/ckfinder/userfiles/files/32961153348.pdfIn PDF document text
    • https://stephan-kratt.de/data/reiterhof/userfiles/file/mulepum.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/16097057846.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=index+of+blue+bloodsPDF 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_off0000ec78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC78 19064 bytes
SHA-256: 0d50e1fa8322a25f84cfc2abca86fdb260dc91a6dbdfac4cebd5823524e201df
font_01_sfnt_off00011dc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC9 10188 bytes
SHA-256: 2e87cec10be3a2a8785286c91751a47bab7e132e5b096be2c0cd8339edd8cd2b
font_02_sfnt_off000134bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1