Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd5da4ffbd10f6a5…

MALICIOUS

PDF

82.2 KB Created: 2021-07-03 00:00:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f02e8d9c831d3ea93b5e0e9261ec3b9d SHA-1: 013071ecaf416d8d86c7ac5c9c9c54a3268d6847 SHA-256: cd5da4ffbd10f6a5064b36028bfbd54aec201d626c0104720df812a29c21330c
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple links to external PDFs hosted on compromised websites, suggesting it's part of a phishing campaign. The 'SE_INVOICE_LURE' heuristic indicates the document's content is designed to trick users into downloading a payload. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://hochrainer-elsner.at/upload/files/velujifireboxasave.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609831cb2b24b---kozidowop.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a587858350---73278003115.pdf
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/70085372920cfaf2d58fe0ca8c1d0978/jemejomidinirawedimufor.pdf
    • http://archissimo.eu/userfiles/files/wezisos.pdf
    • http://unicaconsultoriarh.com/images/files/xixapujiponodesadojekaf.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd0a5034491---51386742712.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/mdf4jqqlrcgv9kemo0bt8js33n/jidamora.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/21d3dc16a4f2ea9b90f69f862ecc3f90/zomunogubojenaloga.pdf
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/06cee95aa930427a0eb78e0dafa72132/nubegivaw.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e4442f3085---59848957816.pdf
    • https://kozhikodedeaf.org/admin/my_files/file/satikoxagagonixegowebiw.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/6b2a10c0202b734328d0b117fb3bca79/15253570532.pdf
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/0215c89438a3b6eb03c978e847ea55b5/73877377463.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/33b796ba2419068547f4b144b999cdfe/gosisubimobo.pdf
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/160867cdb3d449---69187721133.pdf
    • https://manuscripthandler.com/userfiles/file/pudubawugomowowamitimeni.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d76df743fe---lomiterobozepazejunesofuj.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/1067a8ad22504908304e5a16e9660e1e/64682474836.pdf
    • https://susta.vn/userfiles/file/notad.pdf
    • https://i-chat.tw/js/ckfinder/userfiles/files/31065741306.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/5dpi5rilj294o4t1fpmdr0bbhj/vudojigonenenenokulutakeb.pdf
    • https://hansenlight.com/UploadFile/files/43373800221.pdf
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160778da070304---27649102142.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=i+vouch+for+you
    • 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_off0000d6b2.bin
93080f5588cb1df08d788e59b6559a046474ddcc5145b2072178417e98ecf9e5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B2 9860 bytes
font_01_sfnt_off0000ec8a.bin
2ed4d28ebc7a4a0fff06d32ba703555d7d55f2babe07ed2aaec1289c14058048
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8A 21112 bytes
font_02_sfnt_off000121a5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121A5 16792 bytes