Malicious PDF — malware analysis report

Static analysis result for SHA-256 c909f583f41aa048…

MALICIOUS

PDF

81.1 KB Created: 2021-06-11 08:51:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 06985feb146aab2147973b38cf570c15 SHA-1: 609387593a803cbe31587d75e11f683a8252c1b5 SHA-256: c909f583f41aa04899cb9638c4b8211311fca55bc0c7f6ef7082b3b88d4de51e
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are sufficient to infer a malicious attack pattern.

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://crewmak.ru/uplcv?utm_term=kavithai+on+amma PDF link annotation
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/fc5dd5f331aacd77a7d1d781180a6e84/39516055280.pdfIn PDF document text
    • http://suamayin.biz/userfiles/file/59086258261.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/fibigirusovofujatekipetun.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/q187bf81otr914n6kjfcogouag/9777133446.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16072b13dae250---15376531712.pdfIn PDF document text
    • http://domholidays.com/userfiles/file/66043555633.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a7e3bc07ae3---9068154377.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16072100cc7d4b---55137578738.pdfIn PDF document text
    • http://best-infosystems.com/userfiles/file/sekafoxuwin.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/ee8ace0e94933f17e0c363284b92d773/duvezakabogatefe.pdfIn PDF document text
    • https://master-service.ro/images/file/paxezuvaxuralo.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/n6mgdhiea9t7f8curvkpnaqgn5/kubevudivolosa.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/a7bbc591cf02f4d2461ffde88b90f11b/72653741433.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/c62822fa2ddc19e94a1592b3473893c8/rapamadodajam.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c0c9dc63a---misunivinoriziv.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/2e9c343e0f5bdfa9ff4f491095d7bb3f/fikodoxoroj.pdfIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000e631.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xE631 21932 bytes
SHA-256: c1cd0671393c8b1e7deec63509cfebd41983ab4f160f964fecbdaca21181fc41
font_00_sfnt_off0000d67e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD67E 4648 bytes
SHA-256: 9cc38ad3360ecc22f7530908a2013c7ef369cfbe96adf219ec620a73fcd559b3
font_02_sfnt_off00011426.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11426 10252 bytes
SHA-256: 784eaedf382458f861f6db69eac643d6c04f0045c49eb7f4f81d53162e06adfe