Malicious PDF — malware analysis report

Static analysis result for SHA-256 903ef83156107a75…

MALICIOUS

PDF

76.8 KB Created: 2021-06-13 11:18:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: e57ebdb6c15bfe64204d53d2be421c7c SHA-1: 3fe3a44c79d27669fcf890647816962e5a41ea24 SHA-256: 903ef83156107a7509d9e058dda40b147b8eda417494ea70bca9ed403973a611
156 Risk Score

Malware Insights

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

The PDF file contains multiple links, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users. One prominent URL, 'https://infrive.ru/uplcv?utm_term=download+moya+messenger+apk', indicates a phishing attempt to trick users into downloading a malicious Android application. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://infrive.ru/uplcv?utm_term=download+moya+messenger+apk PDF link annotation
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16081cf4e59121---88548283892.pdfIn PDF document text
    • http://banghetretruc.com/media/ftp/file/13003659462.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/75202268306.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7b33cca6d---sowamiwu.pdfIn PDF document text
    • https://securitydm.rs/slicice/file/pidogupomafozajabuva.pdfIn PDF document text
    • http://accessprecision.com/userfiles/file/9225443881.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079bf5c50b52---26894623344.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210505150130251.pdfIn PDF document text
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/3ebbe9e7d25b0e5e99dbb2a071f419b7/15837686636.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/219a2c590fc8a78ef47b3ee515c46b67/vufukovogojubozufodiwawe.pdfIn PDF document text
    • http://mobilesamara.com/img/files/file/83185327434.pdfIn PDF document text
    • https://www.brightfieldbusinesshub.co.uk/wp-content/plugins/super-forms/uploads/php/files/h9dam0pavoi75hcieahm7ecvhv/pusatovexuvulokazimamafu.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/0644d00f0d6cea3bfda1696ca3bb17e5/wenodobupumepudisit.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160b501705d770---2824620962.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/5haj4puqku6m3tjjge1jr910gn/vezubagotodiseta.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/45qr8tqiouq2imr6ecv5g5j5gr/77480677631.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/bcf2551336b638252cf5fec64131afe5/xopewumelej.pdfIn 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB7F 5536 bytes
SHA-256: 2f391ba6f1ea8a1a160132dcb1e7e69533d8493fddafc7ea7a739f3b4b06bbea
font_01_sfnt_off0000fe61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE61 12312 bytes
SHA-256: 66fdacb2d969af28fa71269ed21b8a87433defc84a19953081bedf75094f55a9