Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bf1f4d4430bc045…

MALICIOUS

PDF

91.7 KB Created: 2021-09-07 18:25:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c4cb622d2d3720fbd68fb335a982035d SHA-1: a6379174d26d7e9d57db38964d6e66f50585b12e SHA-256: 4bf1f4d4430bc0456f685c91a61c5b44deecbc7a32a50afcadc1d46b13154b64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm used to distribute malicious content or phish for credentials. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. No scripts were extracted, but the overall structure and URL patterns are consistent with a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://ketchas.ru/uplcv?utm_term=react+js+tutorial+pdf+free+download PDF link annotation
    • https://galerieportelouise.be/userfiles/files/konitew.pdfIn PDF document text
    • http://www.vegagastro.pl/upload/file/sijunomejukiwiwugir.pdfIn PDF document text
    • https://sanipacific.com/attachment/file/wofaxalenasiketavatijip.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/28569226835.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/bifesofovojewufometiji.pdfIn PDF document text
    • http://puginternational.com/ckfinder/userfiles/files/91303132167.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8d0ccb31c---33937261212.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/6sul4b2nhkr80jtla78o0tl8j5/11672984226.pdfIn PDF document text
    • https://aravlicraft.com/cmsCart//upload/file/13789477409.pdfIn PDF document text
    • http://sharon-barron.com/userfiles/files/zalikonidulavixameva.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cb7cc19ccce---11591126260.pdfIn PDF document text
    • http://aldara-latinoamerica.com/userfiles/file/65259351296.pdfIn PDF document text
    • https://media-get.com/userfiles/files/wagalovosix.pdfIn PDF document text
    • https://workinhotel.com/upload/fckfile/35919511912.pdfIn PDF document text
    • https://www.le-domaine-de-hauterive.fr/ckfinder/userfiles/files/menotevosolutidobeko.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b8fc1ae1d0---jusuzubobakowobifatifavu.pdfIn PDF document text
    • http://richfield1962.com/clients/4/47/47516dc9824f3897220912ef171c404f/File/19198272265.pdfIn PDF document text
    • https://calmoinc.com/upload/editor/file/sotowodakig.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1612e8d0c85fe9---neviwefokadiwamo.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130f63ec388f---vatopatuvegapesivid.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160913e6c21d6a---zufizanazafareroninejozat.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bca78854ea9---pogem.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fae4ad135ce---jemijel.pdfIn PDF document text
    • http://cafehinglung.com/uploads/files/kixuximodutupikiduwuliw.pdfIn PDF document text
    • http://swvocal.com/data/se2/file/95462734274.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_off0000f7d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D8 10972 bytes
SHA-256: 0538b98dc65ab04c8a54ce78b76de233e8c77785b59e7d49b13b001a82d4374e
font_01_sfnt_off0001116f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1116F 21236 bytes
SHA-256: 3c9811e4f84ec9be277d937b07807695a3d856efe11b0e0d7afed897a987d5f0
font_02_sfnt_off000148ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1