Malicious PDF — malware analysis report

Static analysis result for SHA-256 987dd9310cfa1e83…

MALICIOUS

PDF

71.2 KB Created: 2021-09-25 07:33:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 774ca6b7a5c4c7c4f5e7f15f4f138a36 SHA-1: 6faa274fdc7734d4edc17ed972be87c77c8b3abb SHA-256: 987dd9310cfa1e83c3291a128c481faf26da6a721403b60209893ac9180cd904
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Static analysis reveals it functions as a link farm, containing numerous URLs pointing to various domains, many of which appear to be compromised WordPress installations. The presence of 'utm_term' parameters in some URLs suggests an attempt to track user engagement with potentially malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://irlanc.ru/uplcv?utm_term=free+stream+fight+tonight PDF link annotation
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1614207c8a6356---28960162253.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/16948229335.pdfIn PDF document text
    • https://pankajplast.com/ckfinder/userfiles/files/80590459340.pdfIn PDF document text
    • https://onlinendttraining.net/files/44091785686.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/kamadujimuro.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/23382782661.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/66238749851.pdfIn PDF document text
    • http://fotografieindex.nl/images/uploads/99451948780.pdfIn PDF document text
    • https://mobilaide.com/upload/editor/file/lisuru.pdfIn PDF document text
    • https://agrando.cz/files/file/47981600880.pdfIn PDF document text
    • https://lazdynumokykla.lt/userfiles/file/kafozixitagebejovevufir.pdfIn PDF document text
    • http://ryanoomen.nl/uploadimages/files/19386120901.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613856f3422ca---zijura.pdfIn PDF document text
    • https://ohcsi.com/ckfinder/userfiles/files/kefejek.pdfIn PDF document text
    • http://diennuocdanang.com/uploads/image/files/padudipalaf.pdfIn PDF document text
    • http://thebookmarkcafe.com/uploads/files/gipasuriko.pdfIn PDF document text
    • https://textmakareknutsson.se/upload/image/6087538933.pdfIn PDF document text
    • https://naveenent.com/administrator/imagetemp/file/nevukewunomexu.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/afae2d934d028d85ffcebb964a56e457/felisatininabibel.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b8caa6f3f1---67514550895.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/27622033717.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/vkvnkva705bbd323b7jlr859l3/bekefuwesafizo.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/nowejorobon.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://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_off0000b30d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB30D 10592 bytes
SHA-256: 132154623b9602dd0a3a282b26483beddfbea6f3b5e4215dcf18183d1f807268
font_01_sfnt_off0000cb0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB0B 17076 bytes
SHA-256: 896e07a1feb095c6fa6226235a698e72b5c64178d6243b55dc414960ad8b1f91
font_02_sfnt_off0000f6f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1