Malicious PDF — malware analysis report

Static analysis result for SHA-256 20472b8fa2d1db1a…

MALICIOUS

PDF

84.7 KB Created: 2021-09-16 07:53:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c5f67600f01037c6ae76635beb69d37f SHA-1: 5c8f1e8164f0845f440c1b3026e98af48ed85e88 SHA-256: 20472b8fa2d1db1a3f3322854573d1c033da2c4db648d06d00bceff83319e9c6
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to external websites, many of which are hosted on compromised WordPress installations. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of a link farm on disposable hosting further supports a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://cructi.ru/uplcv?utm_term=how+to+convert+print+screen+to+pdf PDF link annotation
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142bb6af26f2---didaliganalijilanufu.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109072146249644.pdfIn PDF document text
    • http://minhquoc.vn/ckfinder/userfiles/files/kutimoxaluxedajole.pdfIn PDF document text
    • http://www.truca-taoules.com/ckfinder/userfiles/files/xikililudanagerosetipus.pdfIn PDF document text
    • https://oykufestivali.com/ckfinder/userfiles/files/jetazexakap.pdfIn PDF document text
    • http://japhina.com/upload/file/26213521632.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/90252696615.pdfIn PDF document text
    • http://www.salpasafarit.fi/tiedostot/files/61216842652.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/101031074217.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614157a1b0542---kobuxobafumakarurilij.pdfIn PDF document text
    • http://sprinter-lab.ru/content/File/jozufefesisukonafasajoti.pdfIn PDF document text
    • https://xn----7sbeo1acdy3adh.xn--p1ai/userfiles/file/jigazuxiluvogomebiv.pdfIn PDF document text
    • http://kovove-ploty-brany-zabradli.cz/UserFiles/File/29455578707.pdfIn PDF document text
    • https://searchkar.com/ci/userfiles/files/33513424570.pdfIn PDF document text
    • https://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/73505583384.pdfIn PDF document text
    • http://dalboncostruzioni.it/userfiles/files/98597347051.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/181658865bfda5527769004889515abc/99539369582.pdfIn PDF document text
    • http://prepearl.com/uploadsfile/4738948997.pdfIn PDF document text
    • https://tarsiman.ee/files/file/vafevegafomatofuzevosujiv.pdfIn PDF document text
    • http://majorpropertygroup.com/userfiles/files/7941650064.pdfIn PDF document text
    • http://studiovalentini.eu/userfiles/files/17995237051.pdfIn PDF document text
    • https://blokhol.com/upload/files/46596989775.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16131f6f377e0b---50748312132.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_off0000e6a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A0 17796 bytes
SHA-256: 21ce95146dfb78a33ae64321bfc18f62516277810d38061a96e700aa3980e93a
font_01_sfnt_off000114bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114BF 10548 bytes
SHA-256: 0d6aac003f5d34db86a5087b337328dfb4a0a02de7a48116512f9e439a6b6539
font_02_sfnt_off00012cec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1