Malicious PDF — malware analysis report

Static analysis result for SHA-256 2aaf736606f9f77c…

MALICIOUS

PDF

71.0 KB Created: 2021-09-03 14:49:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: af1e65ed85637eae287dd2aa728728af SHA-1: f03a30f4d83188bad10141e0324e6754e683d62a SHA-256: 2aaf736606f9f77ce45c691f5c47758abcacf9f7e3061f48142e308fc83370eb
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, characteristic of a link farm used to obscure the final destination. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting the document's primary purpose is to redirect users through a chain of links.

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 http://mskabel.cz/UserFiles/File/65873331142.pdf In PDF document text
    • https://livre-d-art.com/ckfinder/userfiles/files/52749415251.pdfIn PDF document text
    • https://activepymes.com/pub/file/faravetowadimikokisalu.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4719f12220---ruganipodun.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/93371091055.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1c05c723cc---96220116677.pdfIn PDF document text
    • https://kurek-rowery.pl/user_pict/file/sagaxus.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/12663666938.pdfIn PDF document text
    • http://marymo.ru/uploads/files/dukinegidojasager.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/stl059nen14fpibqhhv2h5h883/tumur.pdfIn PDF document text
    • http://elitvorota.ru/f/file/tuwuvejimoba.pdfIn PDF document text
    • http://jljemc.com/upload/files/98074743222.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/b1aed26fae0a1ffddc0f7159710e0943/ximofikuvezibixamuvap.pdfIn PDF document text
    • https://kurtoglumob.com/upload/file/zijapexoxori.pdfIn PDF document text
    • http://eprdel.cz/userfiles/file/mikoto.pdfIn PDF document text
    • http://delve-cr.com/uploads/89070783117.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef3dd48d5f---lebosujibezujumipi.pdfIn PDF document text
    • https://sluganarodu.org/userfiles/files/zekirozejesi.pdfIn PDF document text
    • https://galerie-louise.be/userfiles/files/21866988696.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607076627119d---84924126580.pdfIn PDF document text
    • https://cedria.es/DOCUMENTS/FotosFCKEditor/file/87656935035.pdfIn PDF document text
    • http://www.superior-inkjet.com/login/ckfinder/userfiles/files/gujotaginorow.pdfIn PDF document text
    • http://addon-colsman.somantec.net/ckfinder/userfiles/files/fudovizake.pdfIn PDF document text
    • http://elijahlaurabishopblack.com/clients/b/be/bed082b287f5bb70db4763ab929fc18a/File/wisanomejemejulimikini.pdfIn PDF document text
    • http://rustproofingottawa.com/userfiles/file/nevepeferifowo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=glucosa+valores+normales+pdfPDF 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_off0000b61a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB61A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE31 10796 bytes
SHA-256: fee212c3fd4141818c92384c3f03c1d3934680a57ce452bb07442c6043cf57f2
font_02_sfnt_off0000e71a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE71A 15996 bytes
SHA-256: 2b6fdc98e228faa205325415e5ccbf8e56f23a0344fa34b5b8442eece30676e0