Malicious PDF — malware analysis report

Static analysis result for SHA-256 826e088dbbc0a934…

MALICIOUS

PDF

81.6 KB Created: 2021-09-20 10:46:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2f74f1d2bdf048d5763727b442d77d4f SHA-1: 28f436ccc86d5e5b1db2d9ced539bf0c59d1484c SHA-256: 826e088dbbc0a93438619e42299fb95edc58b8a06ffe8b10a2da4d9fe4379b0b
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The document body is heavily obfuscated, but the presence of numerous URLs and heuristics indicating link farms and compromised uploads strongly suggests a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://nexxstep.nl/userfiles/file/xofowomosabonalak.pdf In PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/c8614bde6d8b30679391d389eae8b21e/92217410381.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/34650214774.pdfIn PDF document text
    • https://nls.vn/upload/files/61230306250.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ce55a8ed30---24241848813.pdfIn PDF document text
    • http://knipia.com/userfiles/file/8351294137.pdfIn PDF document text
    • https://viadagio.be/userfiles/file/dokidebunesigajutek.pdfIn PDF document text
    • https://homeuu.biz/upload/ckeditor/pages/files/wowuxoremivezovizajaba.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb188137be---28693226017.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/54238038734.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139a444b78e4---49786269167.pdfIn PDF document text
    • https://ever-progress.com/upload/files/28722253872.pdfIn PDF document text
    • http://banglatalkies.com/dynamic-images/cms/file/9072025502.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/48019430276.pdfIn PDF document text
    • https://vnmmalta.com/userfiles/file/kabazifebizuzorozep.pdfIn PDF document text
    • https://portalbime.com/UploadedFiles/New/file/4431951371.pdfIn PDF document text
    • https://xn--atpta-nfb.lv/images/userfiles/files/joxubunumolusalaxotawo.pdfIn PDF document text
    • http://yangpupark.com/uploadfile/files/bumidovodobesi.pdfIn PDF document text
    • http://opsir.eu/files/file/30852479662.pdfIn PDF document text
    • http://khonggianxua.samdigroup.vn/app/webroot/upload/files/32256497846.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/86316199067.pdfIn PDF document text
    • http://agronlogistics.com/userfiles/files/zujawin.pdfIn PDF document text
    • http://www.serge-valentin.net/ckfinder/userfiles/files/sigigosowapigi.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/2021090111102140613.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=best+alternative+of+camscannerPDF 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_off0000db69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB69 10616 bytes
SHA-256: cf021e06de9d85c41cf93fb4f9d50cc77ba5fb203c4aa9fae0da015363ecf8a4
font_01_sfnt_off0000f3bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3BB 17672 bytes
SHA-256: ec1c2abdcfcbffd26b790dd1a0c78b6533b343954aefcc64c6b6d316889641e5
font_02_sfnt_off000120d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1