Malicious PDF — malware analysis report

Static analysis result for SHA-256 913309bfbe5a9908…

MALICIOUS

PDF

100.0 KB Created: 2021-06-24 13:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 412a88b172c840f13e7edcadb81a3a60 SHA-1: 59a3a545771f96b1678643ae94f53ba08cda4ca2 SHA-256: 913309bfbe5a9908610c80a8809856ad09229320b38a2a47c3ac3bb98d786e20
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to compromised WordPress sites, indicating a link farm designed to host malicious content or redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, specifically identified as a phishing trojan. While no scripts were directly extracted, the heuristic firings point to a phishing or malware distribution scheme leveraging compromised web infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b8f3d003fcc---55947888109.pdf In PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/160a77ca8a7cb0---78189421727.pdfIn PDF document text
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/fb864b16d9444a464b561192f5a61b7f/teluwibugipazedalateve.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/vodupepovewoguguwikitev.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/d2308dae9899da845a7c6cb5630978db/buzedepabaxotufida.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce42056c5ae---26249310188.pdfIn PDF document text
    • http://cymrozgreatdanes.com/clients/1/1a/1a407d8ccac5525c71aaafb6b4664123/File/wagebenirixuz.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/f3c239e5a0512959b1601b9d1c0f8425/golezinalazir.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e52027f74f---kapavurekox.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc82239113---4947456910.pdfIn PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/72efaf3961f11bbbddf3f2d1f3b90659/60466000329.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/96663650853.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a096247a697---buzobudesa.pdfIn PDF document text
    • https://tennis94.fr/img/pics/files/jaxomapi.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/50709220757.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d366f004c82---bowijodosif.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/3284be621fa20d2d5e740788dc04a5a8/25430571748.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160a34b927ea62---96749584274.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=nikon+d60+manual+settingsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013617.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13617 3312 bytes
SHA-256: 082c89522e4251f0a814862fddf633b1dac669eb780a02580130c1f52bfffe84
font_01_sfnt_off000141f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141F8 5376 bytes
SHA-256: e38f70d8f6d1bd83b4138f5c2179ebc16a588b90e6254a07ed75f9aba5840288
font_02_sfnt_off00015434.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15434 13784 bytes
SHA-256: cbe518de40a42f0d53ca08f90a408e77df63959e6bb613a51f1f1de8d4345297