Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0599b9a0aae0a58…

MALICIOUS

PDF

86.4 KB Created: 2021-09-19 05:06:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1746ce11ba215ca22c490af0f6e14269 SHA-1: 664ce07416fb9a2d0f41b6cd95e56dcbe4d30b4b SHA-256: c0599b9a0aae0a58120dc383a80073ff271706474bc4b933a8ed6248cb0d7926
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as a malicious PDF by multiple heuristics and a machine learning classifier. It contains numerous external URLs, including links to compromised CMS uploads and disposable hosting, suggesting a link farm or phishing lure. The presence of PDF_URI and EMBEDDED_URL heuristics indicates the document's intent to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://inwebjor.ru/uplcv?utm_term=new+movie+online+watch+app PDF link annotation
    • https://www.nstoplana.rs/ckfinder/userfiles/files/bivowetedupofo.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/fobezokedobo.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/35647967738.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16136c985d0f91---5229649378.pdfIn PDF document text
    • http://geoplan.su/userfiles/file/geweja.pdfIn PDF document text
    • http://kaitosushisb.com/uploads/files/kevojunori.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d448a8f3b---vujaj.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///2021091644732_279599530.pdfIn PDF document text
    • http://tnmetalworks.com/images/files/40137928168.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612f2d9550127---52436069660.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/21582481561.pdfIn PDF document text
    • http://crescentcarpets.com/userfiles/file/mebatukeput.pdfIn PDF document text
    • http://jubangh.com/Upload/FckUpload/20210919file///57957993501.pdfIn PDF document text
    • http://tandprotheses.com/ckfinder/userfiles/files/42578737152.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/11069697992.pdfIn PDF document text
    • http://pastoret.it/userfiles/files/mubogorusida.pdfIn PDF document text
    • https://lexcochoralsoc.org/demo/lccs/beta/userfiles/files/93832063898.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/b5993a4d05eae206d1eb81c3c40312a3/xirevaf.pdfIn PDF document text
    • http://haphadoor.com/upload/files/tirazazisev.pdfIn PDF document text
    • https://losaltos.com/wysiwygfiles/file/wopopizefemurebimoz.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-9-12/20210912023018967586.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/77716385053.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_off0000ed22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10534 18192 bytes
SHA-256: dcf48d1d4db4dec9860629257d21b4ae0a53fffb98a4dc5c29abc02bb3227804
font_02_sfnt_off00013487.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13487 10500 bytes
SHA-256: a056188ec7424c5c602d8c668250ca78e846511798f33402abf8cd27e114e957