Malicious PDF — malware analysis report

Static analysis result for SHA-256 50fc9dffefbefe40…

MALICIOUS

PDF

78.3 KB Created: 2021-06-20 23:33:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 0d6994b11d4101d24ec65cb72b2ab33f SHA-1: b5dd43234d0dba0102de99331f86b735bee4dfde SHA-256: 50fc9dffefbefe4026afdf85942e01ce7f66dccc78406f39d44fe5e03d36a93b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, some of which appear to be compromised WordPress installations. The presence of these links suggests the PDF is designed to redirect users to external sites, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=drawing+anatomy+step+by+step PDF link annotation
    • http://arunimaflavours.com/userfiles/file/senelikisusujomelu.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16086eb57764ee---46153625910.pdfIn PDF document text
    • https://area5srl.it/file/6018234076.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16079b27f77957---ruresezajamososudokez.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/5mft0dbfmbiljg5hlr3rotlp38/rofofeb.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/16b5470087216fe7fb1f9604a0a0a520/83390455157.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16090eeb292109---xomoxasegigovexezeda.pdfIn PDF document text
    • http://vodnik48.ru/content/file/2193608047.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079edfa9b5b1---wolowipenoxagosexa.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d308d5ca1c---dajizivis.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abaebd715f3---2873876604.pdfIn PDF document text
    • https://emauto.lv/index/images/up/file/67950333073.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608556335b5b6---38334669935.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/55923066265.pdfIn PDF document text
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/51914386622.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000dffd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFFD 5440 bytes
SHA-256: bb979ff81367dbd5ac0ec798e5e9329498991d9b239747a577f78c89d9f18a9a
font_01_sfnt_off0000f284.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF284 10432 bytes
SHA-256: 0e59c11a54ab2f9b33f3d9b71db3270b6828bed87169f47ef4197aab6a289822
font_02_sfnt_off00011620.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11620 16060 bytes
SHA-256: 99ddc6f5858eb134f8024171ebe717cbd02485c31471b921a5021903b5272953