Malicious PDF — malware analysis report

Static analysis result for SHA-256 5433fbfd3427d899…

MALICIOUS

PDF

117.4 KB Created: 2021-06-26 18:46:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 44635038f3ae496b10a5ee202911a2f3 SHA-1: b00f27c30ce47a86ca9f7b0a34b45216cbd60ff1 SHA-256: 5433fbfd3427d89974f377681a7f3b091f1815db1a6b49e274be997da1809795
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing. While no scripts were directly extracted, the nature of the embedded URLs suggests a phishing lure or a redirect to a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9941

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160d7325a2db32---7591120273.pdf In PDF document text
    • http://www.awakohchang.com/image/upload/File/ewulilegesuxumaravagis.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/budizo.pdfIn PDF document text
    • http://garantc.ru/userfiles/file/lidamifijotugosizo.pdfIn PDF document text
    • http://castudio.eu/userfiles/files/sajebotinuguxejiduke.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/kdknvlq78skcfu9tk7ftq8slsl/bevod.pdfIn PDF document text
    • http://suachuabaoduongmaynenkhi.com/img_quanganh/files/ramosebodivonitujox.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/ta19g14tk76gosk6b16e6qbjt1/41668679950.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160804d2552ed1---32693226189.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/8b4f0bbfd4dae94a67ca6f96081b092c/5221942134.pdfIn PDF document text
    • https://egyseg.eu/ckfinder/userfiles/files/66790637783.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/ial7sa3igip386u2tc0i8e3nd6/5751624738.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/5mr8ok2np34j9j0ro731i2bui0/vukuniwakimanikodef.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b064c141e0d---gawunosusisalaban.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/61168150604.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160741812e6b60---vojakezupazovolof.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f733dead1b---75042788246.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d51a85ae26f---vilegamakubojimo.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160a96b1683c6f---pokefixewutovukikeligev.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/dadejefaxame.pdfIn PDF document text
    • https://radmangroup-ye.com/rgfiles/file/22576586514.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/hljc59j129v07sii12t6u9tlad/63303100880.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/f8a06a95370ba917e995b3a5c6090105/8454665989.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+cite+apa+website+without+authorPDF 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_off0001699b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1699B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000181ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x181AD 17712 bytes
SHA-256: e2b5321cfc722c220f4b968871f86744ee8a7bd39f20db54e3ac851c77908f75
font_02_sfnt_off0001affd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AFFD 10640 bytes
SHA-256: c8635c0e85cf985b826977b1e7f5cc1b2e5aa16edede8c59bc82cf3c2d1c5e24