Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8b1618b15698f1f…

MALICIOUS

PDF

71.7 KB Created: 2021-09-25 11:13:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 0b55a46861f91059f905d0c3acdde010 SHA-1: 1c905546dccab294c218ebb11dfac163e84f4165 SHA-256: f8b1618b15698f1fc84b0bf6175320482d5c8c528a1a953b9e89ee7eaaa4c8ba
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting. The primary attack pattern involves directing users to external resources, likely for malicious purposes such as phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://highdesertrent.com/newsite/images/uploads/file/64019812353.pdf In PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139bc8a396ac---87811842807.pdfIn PDF document text
    • http://wizclub.net/upload/userfiles/file/tasanejevofuxi.pdfIn PDF document text
    • https://khabul.mn/mmpa/userfiles/files/81480126257.pdfIn PDF document text
    • http://scpt.it/userfiles/files/nerufonutelovub.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614af3a1c3297---gulufakojesemuremukuwor.pdfIn PDF document text
    • http://chinahongji.com/d/files/bizidux.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/14113309273.pdfIn PDF document text
    • http://thibangoto.com/app/webroot/uploads/files/10677047278.pdfIn PDF document text
    • https://salwangurugram.com/files/razixu.pdfIn PDF document text
    • http://www.cenlafilm.com/siteuploads/editorimg/file/jixegaxibatexigit.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/797dd515e224c4f3e82021a6c796cd31/vugikekelovipexewule.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/10237185215.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/zofigibi.pdfIn PDF document text
    • https://borgopitti.it/userfiles/file/81731863392.pdfIn PDF document text
    • http://limoride.net/gallery/file/29116023575.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/97566405975.pdfIn PDF document text
    • https://newdesert.pl/userfiles/file/92380716363.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/pumomobezutoguwosemot.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/63595435803.pdfIn PDF document text
    • https://turystycznapodkowa.pl/userfiles/file/87001395037.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=latest+android+sdk+free+downloadPDF 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_off0000b3f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3F9 17572 bytes
SHA-256: a58960339066b26848d0dccdec4f5b49cd105cdab8af4dc2665c1de3685b43cd
font_01_sfnt_off0000e10b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE10B 10484 bytes
SHA-256: f79d4c068f9929286f475b002620b57ae1afa7ee75015d04aa9c74ae715340bd
font_02_sfnt_off0000f90f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF90F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1