Malicious PDF — malware analysis report

Static analysis result for SHA-256 db88ec4279a8e384…

MALICIOUS

PDF

78.7 KB Created: 2021-06-19 18:47:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 87db9f536e3ee29819ec339b95d20443 SHA-1: 8377ad90d49623aaffc2a254849a09ce25913188 SHA-256: db88ec4279a8e384a4aaba8c865346d567da0b332c3e176df00e88b48b161679
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple potentially compromised websites hosted on disposable domains. The presence of numerous unknown URLs suggests an attempt to distribute malware or conduct phishing attacks.

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 http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609873ae64fda---12396404726.pdf In PDF document text
    • http://parkhigh65.com/clients/4970/File/28948289912.pdfIn PDF document text
    • http://tortsurprise.ru/upload/redactor/files/gudadulusekutem.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/55505685425.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/5e1f8ad2b9c292a7aa7e21146382c976/pofisifa.pdfIn PDF document text
    • http://evpltravel.com/xv_image/file/11744094768.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607539faa4301---71983305916.pdfIn PDF document text
    • http://reguitti-engineering.it/userfiles/files/25708229467.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8a077aaa8---12643877180.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608d1560592b0---62546467855.pdfIn PDF document text
    • http://kulturazebrak.cz/userfiles/5696054936.pdfIn PDF document text
    • http://pusancard.com/userData/board/file/825812158.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b48dff080c1---97150094468.pdfIn PDF document text
    • https://srmhospitalities.com/images/bulk_images/files/74746801303.pdfIn PDF document text
    • http://bpabv.nl/uploadfiles/file/tunogerojofanuk.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/c4ccf571ac216d267f737562c6c6e61a/33834705557.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=quiet+place+2+2020PDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e650.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE650 4652 bytes
SHA-256: ec0fe5737392cd4f9812770132edfd4ab8ce88487c0c6e2a94b82bf19ed7c13a
font_01_sfnt_off0000f628.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF628 11792 bytes
SHA-256: 5b8e398369bc8009c9f55183dc5c6592575b7d01ae32fddbb27d2037f761e4a5
font_02_sfnt_off00011e0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E0A 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34