Malicious PDF — malware analysis report

Static analysis result for SHA-256 35af869d144135a7…

MALICIOUS

PDF

79.3 KB Created: 2021-09-08 09:14:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 247841c8272d9f91724d3c8c9f1bd7ea SHA-1: cd818cdd583a04ccea85c49ec95b4b7d674eb462 SHA-256: 35af869d144135a7d750f63f28250777e707aee588a7e2c3c34f094f867c3e1d
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://akcompany.vn/uploads/userfiles/file/zapaxet.pdf In PDF document text
    • http://khmim.com/ckfinder/userfiles/files/38790522733.pdfIn PDF document text
    • https://whiteplacard.com/UserFiles/file/limilimunopaw.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/1521052eef86c04f7de249b415afb672/xopatebenasujijale.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aae9e225598---rekuvobodobusogapez.pdfIn PDF document text
    • http://cablexconsulting.com/Upload/file/rapipenixijik.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/vuxibona.pdfIn PDF document text
    • http://goref.ru/files/file/xiraxaloxakidu.pdfIn PDF document text
    • http://worldcar.jp/userfiles/files/jexusefojateviniwulin.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/18226061589.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608547c7177cf---63443512763.pdfIn PDF document text
    • http://www.chp.pl/ckfinder/userfiles/files/serujod.pdfIn PDF document text
    • http://olguanaokulu.com/upload/file/21050336858.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/9r1hs20b8grjr4jaivpr6thuk0/40645242661.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/1713b8f02bdb1c132901354d79482cd0/tevatoluxetag.pdfIn PDF document text
    • https://idd.no/ckfinder/userfiles/files/meduxigibumafaragokefofiv.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607616d9f065f---12205285111.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d79f65f10ba---digitomurozoj.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/muwulolujavulitetowotunan.pdfIn PDF document text
    • http://putzlappenborner.at/editor_up/towojozuvoxi.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/bakakobawuwelevegilile.pdfIn PDF document text
    • http://fenotropil.ru/userfiles/file/95590539025.pdfIn PDF document text
    • http://askort.pl/Upload/file/18909323098.pdfIn PDF document text
    • https://confetti-seasons.ru/upload/files/25868186704.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=exercicios+de+resistencia+muscular+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_off0000d10a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD10A 17868 bytes
SHA-256: b3211c999f173ede31408baecb7f95db4d97437e9f08507e4c5ce066a810f4af
font_01_sfnt_off0000fe1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE1C 10964 bytes
SHA-256: 938f7968bc23baad451f6042f6ba06041e51cd7240ae5335ec960975d00281ec
font_02_sfnt_off00011792.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11792 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1