Malicious PDF — malware analysis report

Static analysis result for SHA-256 261f1436a01b739c…

MALICIOUS

PDF

86.3 KB Created: 2021-07-06 17:03:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: f2f6a0f62ea415dabd13d8aa16264627 SHA-1: 6256c75c7012736a69c0210066640be6c07eebdf SHA-256: 261f1436a01b739c0a5c46f37fc2548ff38b83e4ce371ec92e0492fc0f8b3b23
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the PDF structure and URL patterns are indicative of a common malicious document distribution technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://allytemp.ru/uplcv?utm_term=types+of+letter+writing PDF link annotation
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/sv1hjt1looubli1emdfd8n5hu1/63051704832.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/es6opulsuq1bh7j2v0niviodgo/givejalobuzasun.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/bfb139015601df5aff4d6ef3d38f32d1/fefukex.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1606cada4325eb---nofetadubefijaj.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/84898965705.pdfIn PDF document text
    • http://xlsferrosilicon.com/d/files/goveraxoxujolunamete.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160918a6a2acc7---tekoridigifokugiposonav.pdfIn PDF document text
    • http://odmooregolf.com/clients/e/e7/e7046aca88cfcc92de0be8f3f6b3de3d/File/kojomigenujajusukivapakom.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ab26e5e6838---61389129386.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/5ftqrb4qeeo9r1uat1q1j7a6s7/15618586592.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160832f7a5bcf0---rebiwuxeredaguned.pdfIn PDF document text
    • http://stjconsulting.it/userfiles/files/dalepuxelejadevomopo.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/922bdcf2d5bbc29e28c334b08978c500/2170032033.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/63544181860.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8304322e8c---jetipodideduradu.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/tqbbnqumlqdurgfdh8j40p7b61/luxavimawe.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c85589743cd---15068103947.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/ad714a8382101873a3a270b97ccbb2be/veloliwumupema.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/vanaxuwi.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/prtcnrbsq4lkddlaphh4u6e1d0/votipoxulariradako.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/21336915734.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/9c5e8629974580d8ab7e5c7a95047c23/xaxixorafizilurefufozosil.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082441167646---kapozexitug.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/hlfuk01q83ebpfr3mab9o08ad1/risizilax.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_off0000ef4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4D 10536 bytes
SHA-256: 3a433ae52e86aa1f1bcc54ef256ac1a1f2ad6a8e576de9ace4e55b7a606db304
font_01_sfnt_off00010785.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10785 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F97 17148 bytes
SHA-256: b6e6aab13d76dedc12d4cb38d3216636a5b48ee019e7a16b0a5ba2537255e56b