Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b8f1dbd3308e06b…

MALICIOUS

PDF

86.5 KB Created: 2021-07-05 11:24:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 317b98b6fed311831b3964ba323d7301 SHA-1: da661f4b5573d12ccf3931a291a42157ef829bbb SHA-256: 8b8f1dbd3308e06bc940f6aceb128c1cde734af8cc5c2a59d5d5de7950de9387
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which point to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content to analyze.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://ipmarketing.net/userfiles/file/jivejetubadota.pdf In PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/188da605f68d396f210a800a3566dcc3/mojaloboliriwatipis.pdfIn PDF document text
    • http://cambridgekapurthala.com/damana/userfiles/file/60004665418.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/cj3u9ni1las5jf8g8jslak49an/56557650279.pdfIn PDF document text
    • http://okfilm.kr/userData/board/file/2594942025.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d99558054f---41399612948.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b89252e35c7---fulenoxu.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/3f6p22gk2mj0bplkqdqcn2akv7/lowuvi.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ee2a7d56d---borogitagozarebo.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/43e7ea309f9b97e5a43163beb11acc10/91366545149.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160ade38597fe0---detaw.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/ac020615f58b222ff4209850894adc64/mijufoguzeb.pdfIn PDF document text
    • http://julianowka.pl/ckfinder/userfiles/files/62258074943.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/e5250bd929b734d59ffa021674e8e04b/ravurijipufexusuxut.pdfIn PDF document text
    • http://srsheicha.com/uploadfile/file/46055872897.pdfIn PDF document text
    • https://aspit.ro/imagini_ws/89878476682.pdfIn PDF document text
    • http://m2m2design.com/userfiles/tasemo.pdfIn PDF document text
    • http://dagmar-e.de/userfiles/file/38402750945.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af8928bd1a8---rumobovarugevov.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/3b9cf3a322b0f031cdcd5521734349e4/zofedaw.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9b41cc4d1a---47377028596.pdfIn PDF document text
    • http://www.deopendeur.org/imgUser/file/zevufupulawizewe.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/nilopasexapezij.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/edhglnmlegli5ulbqfbot9fak7/vasurofuzu.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d5bcef3e5---zugowogakemogolaxatebiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=mgo2+lewis+structurePDF 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_off0000ece8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE8 18068 bytes
SHA-256: f13bb14ce23694512acbe4183b6fe11ff9cef5d7d8f678e126c6f0ee723afd1c
font_01_sfnt_off00011ccd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CCD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000134e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134E4 10436 bytes
SHA-256: 78e9db496208945388bce23cf0c2e8e70b736c5c09a1f257a177126e70588550