Malicious PDF — malware analysis report

Static analysis result for SHA-256 b39cbeec52f3e5f7…

MALICIOUS

PDF

89.6 KB Created: 2021-07-03 00:56:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: f1318cde60144a31fcec93f0d739da7b SHA-1: 16e5478044e03456e01f7f73138d1296073cea4f SHA-256: b39cbeec52f3e5f711030eaa1d83bf17f84807d139442e23085a3ace9adcb679
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it functions as a link farm. The primary purpose appears to be directing users to potentially malicious websites, likely for phishing or malware distribution, indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://synerhu.ru/uplcv?utm_term=why+is+my+dog%27s+tail+shaking PDF link annotation
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160daaf6a1d570---56581656762.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607daecb72ab4---4213207463.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/ar108ctg3r2rnasd5hn1ooqt20/55875696754.pdfIn PDF document text
    • https://98ing.com/upload/ck/files/20210626_222749.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082a60f9c7ff---sataz.pdfIn PDF document text
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/92e7dacf67375eb3d437de993a124ad9/83343056700.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/kt9lj148tgko2d87a802gv31oj/99388423362.pdfIn PDF document text
    • http://teenaramainc.org/clients/875997/File/rulabopeti.pdfIn PDF document text
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081b322511b4---22295302576.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/34fe54636bd6693ba3638fe4cbd9286c/funofisoteloluxapapo.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/e03sddr2dmsl2u8g6r0nj81mtu/tisexoguwo.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/jqmoagvaf3p022q0n5bicr0eo5/ripenelaketiwanoxawixuvof.pdfIn PDF document text
    • http://montgomery71.com/clients/34132/File/soxapikimo.pdfIn PDF document text
    • https://discovercefalu.com/_data/images/file/ripikekunowegipaw.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160abd435d2b65---97643434905.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/d3ee5cf34786e240e18df3d41096a7c2/27521421709.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f1bc02fea---97893544992.pdfIn PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/108ed491eb6a1afc05661dc99e3bce7d/40489264809.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607886f1d586b---punonawuzovitasolaputot.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/0c053ee585beb9d36a6bcdbf2eeb9be1/sezoxijusifurokigare.pdfIn PDF document text
    • https://idd.no/ckfinder/userfiles/files/2133538603.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1cdb204a3---66476912235.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/b1325f635c733fbe7124b4fccc08fa98/51703227479.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/jikibomakotusujebidaweda.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607937cadbbfb---61643596924.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/2d0a96b0230bed82f33b816b191b32d6/ruwididewibedezeduw.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_off0000fac1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAC1 10696 bytes
SHA-256: bb8e547469ac08dff93c804ea1050c350f829a6e0d5ec032b7f2c38c536114c0
font_01_sfnt_off000112e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E9 17528 bytes
SHA-256: 35e9be3deb38bcbdc06accb165cd053b8d230a947e3a17462e0336e41f62fd66
font_02_sfnt_off00014105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14105 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1