Malicious PDF — malware analysis report

Static analysis result for SHA-256 16885c6299152090…

MALICIOUS

PDF

83.5 KB Created: 2021-09-06 10:56:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c683ca63f48ec26008af767a2c7977f6 SHA-1: 818918b7d1eb77ce0f63f89d8b2905f0ed47dfa1 SHA-256: 16885c6299152090d00d5902233f892a8387a6100278e1758994a24b69be473f
192 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is often used to redirect users to malicious sites or download further payloads. The heuristics indicate a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to obscure the true destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 9

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.rosabrockenhaus.ch/ckfinder/userfiles/files/vimigakojilipukejopuju.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd1d41de22---fobesiga.pdf
    • http://civicwomen.com/ckfiles/files/retux.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ae8c8510d32---88505406727.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/h63ug299efbejv52cbh987mr32/wukakotug.pdf
    • http://vytvarnyobchod.cz/UserFiles/File/80557955749.pdf
    • http://haphadoor.com/upload/files/16789215131.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/5e3f69094191bb21f1a07109a34b4539/nuwejisurunodekejulifizo.pdf
    • http://dailymaydemtien.com/userfiles/files/3947189729.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b0c9cbbe926---gewadizubulelinexuve.pdf
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/9c3cdaoso8vji69pk5m7eero8j/51957544728.pdf
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/pua3lesep4obodgc0u61cmgk17/24143655456.pdf
    • http://ankaser.com/userfiles/file/juvoxitosaropufogokome.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/11153b54b38de78d8bbbd4c1cc4a208b/17459671972.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083a38a14b33---806278681.pdf
    • http://agiusfuneraldirectors.com/files/file/6912720891.pdf
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/mitipazeda.pdf
    • https://empezo.xyz/js/ckfinder/userfiles/files/33195638166.pdf
    • http://kennedy-jackson.com/clients/f/f7/f78508644b517540cdb1549d93860f53/File/lunifidaferiwupeka.pdf
    • https://baoholaodong24.com/userfiles/file/tixakoxuwudu.pdf
    • http://houstontca.org/Content/uploads/files/61215344712.pdf
    • http://cowmoo.org/ckfinder/userfiles/files/winetojarawusakexan.pdf
    • https://curtain.jinware.com/upload/files/fugeletipum.pdf
    • https://krzczonowice.pl/gfx/file/4319449503.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c324cabc81b---bewopabisuxibanapu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=sap+sourcing+and+procurement+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df6e.bin
9f2ff22623e949f3dca6991bee17829fb73756cd379f6e18a7f6246ed1d491b4
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6E 11092 bytes
font_01_sfnt_off0000f90f.bin
97ca861ea9e80c02ba035d9d8c45da35f636de76d7a7aab719a4ceed1150b904
pdf-font-stream PDF embedded font (sfnt) at offset 0xF90F 18208 bytes
font_02_sfnt_off00012838.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12838 16792 bytes