Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9af512fb1a0bf27…

MALICIOUS

PDF

87.9 KB Created: 2021-07-18 11:48:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: d9f6c1efdc9d0b2a6bc64b74c4023870 SHA-1: 76b50c2cb2887dfcac2e2d247cf5eb646a1e6fec SHA-256: e9af512fb1a0bf272b121529f983d4fa2822462933e3675482762f9ae125df08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV. It contains numerous links pointing to various domains, many of which are hosted on compromised CMS platforms or appear to be part of a link farm. The presence of these links suggests an attempt to redirect users to malicious websites, likely for phishing or to download further malware. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://cka-shiba.com/ckfinder/userfiles/files/juxowegutirosadekosufopi.pdf In PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/87303395376.pdfIn PDF document text
    • http://oilandgaswork.com/userfiles/file/tinoxenawugujenebime.pdfIn PDF document text
    • http://shsclassof1959.com/clients/a/a7/a7a82b2a6025f7fafce5d77be70bf845/File/12396535598.pdfIn PDF document text
    • https://securitegenerale.tn/userfiles/file/51113875892.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/aj7am27mcr18cg1nd0mdfbojap/18201385646.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16075e6b8bfe7f---4755744089.pdfIn PDF document text
    • http://el-system.jp/uploads/2012/files/13847781972.pdfIn PDF document text
    • https://tigercabinetry.com/wp-content/plugins/super-forms/uploads/php/files/26ca2aac0931797966808e8f23a36b11/92317226031.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/dba403a337b8f0f270fc53f2f126cc64/78287589820.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b03adc95382---tupijizasiz.pdfIn PDF document text
    • http://donghocasiochinhhang.net/uploads/userfiles/file/rutuxaxufupojodosijabib.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/3ekvpbapoostisepait3d8f57k/liburotagi.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/wasedotiwalavuzobuzitu.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/3rn1gbl3ukpb9d0sujei2judbs/62719373220.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/69998601628.pdfIn PDF document text
    • http://fitviewer.biz/files/file/68740584769.pdfIn PDF document text
    • http://activesolutionelectric.com/images/file/57270512140.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160719b0f44b03---95349013036.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a48af5dfebf---36072110240.pdfIn PDF document text
    • http://etoprosto.ru/ckfinder/userfiles/files/tonudukiwojewisiweto.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/ceb9vha72a232dum8l9ffotb1u/nusomibokuxumewo.pdfIn PDF document text
    • http://fizjoactiv.eu/Upload/file/masosaselozorexi.pdfIn PDF document text
    • http://thegreenlegacykeepers.com/clients/e/e8/e8dc17949b7ef813e9937e453902477f/File/97575466458.pdfIn PDF document text
    • http://bpsstudio.hu/uploads/todagifuxuse.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=best+android+app+to+catch+a+cheating+spousePDF 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_off0000f4ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4FF 16996 bytes
SHA-256: cf1e3b8afff67fb90c5b01c7a44ee9058cc15778fbe0694382a798a0d7c464d1
font_01_sfnt_off000120f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120F6 10900 bytes
SHA-256: 79ef97819b1e06ae895c729181bebaea41e7be4977a6b17529bd7aedb05ccd7d
font_02_sfnt_off000139f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1