Malicious PDF — malware analysis report

Static analysis result for SHA-256 f55ae245abe09399…

MALICIOUS

PDF

140.7 KB Created: 2021-06-20 11:43:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 279fa31f160eaae38b1baa5d6249c033 SHA-1: 6fb2c8a3b0132bb3d3b12eeeb5ec536cd046281e SHA-256: f55ae245abe09399caf799e191f60d07492058a225136f98396325557b488ac4
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to distribute malware or conduct phishing. The presence of embedded URLs and the nature of the heuristics indicate an attempt to redirect users to malicious content, likely as part of a phishing campaign or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/5f3081bcf663d127da98c4b2b64a36f5/60244598523.pdf
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/355b68c9a2c94075ad03676666178cb0/tomovalotetetabuvu.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c5b2e4d75b2---vaxepagagamemekimezifisu.pdf
    • http://brukbet.com/user_images/file/wazezinefomivo.pdf
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/ccb1896f7073cd58c259dddb2a851861/80443710021.pdf
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/183j7ed2rkdn5s9cuu4ck7c8qc/lilog.pdf
    • http://rafaelokazakov.com/file/42082927682.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/392pdrp7hket9nbd5u6lto7out/64790150972.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fcbf33d880---59874190455.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a627e0a33e3---doraz.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/2i1uij67leak5lmr2iq6740871/40149461437.pdf
    • http://zonweringnederland.com/ckfinder/userfiles/files/96159968920.pdf
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cdd28877a5---jevujaxor.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/7da1df36bcc9070b0f53d39b02512b89/82344878754.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=permutation+and+combination+rd+sharma+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001c61e.bin
d231c4dfeb6db1ba10c08bf5602fe44ed3b88e529fb7738779a5b68693e8cc6c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1C61E 5384 bytes
font_01_sfnt_off0001d829.bin
2fb4c7d1c0f33f2b5b47bdbddf131adae0e77494fab708a5b65d39c3d59ac3e6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D829 11368 bytes
font_02_sfnt_off0001ff04.bin
e335f1697e09ef824b46cce5faafcd1dc34097d002cd4d9bddcd2234082b8d91
pdf-font-stream PDF embedded font (sfnt) at offset 0x1FF04 16212 bytes
font_03_sfnt_off0002143c.bin
ce7e2e230a41ba6fc2d7d2240890c8289d67876d84a3d076d67c0b48111c8230
pdf-font-stream PDF embedded font (sfnt) at offset 0x2143C 4324 bytes