Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdb3df2c0e8fa359…

MALICIOUS

PDF

102.2 KB Created: 2021-07-01 13:58:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: da357c5ffe4ccff6bb5380a31e17a092 SHA-1: 188e77e6147eae3edb1b0bf2551872e1137c0852 SHA-256: cdb3df2c0e8fa359eff0010f14f468c6145dc69f94473e5e332887b7f5a517cf
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the presence of a link farm and the heuristic firings suggest the primary purpose is to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9790

Heuristics 6

  • 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.
  • 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://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ecaf188e2c---32735305507.pdf In PDF document text
    • https://livres-d-art.com/ckfinder/userfiles/files/sigeropafimojabur.pdfIn PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609b414c6884a---tojopegafes.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/80571f702b30a233d61044e4da21aa45/80100199609.pdfIn PDF document text
    • http://tokyoracing.hu/userfiles/file/6209990439.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/dff1f3c9bf214f5f5c64a3bfaac5b5e1/80004371310.pdfIn PDF document text
    • http://kaies.cn/upfiles/2106091318066404934vuxlh.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/6d268928e1b7aee399025cb2e9de6919/jonitugixilesuda.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/33d0d72636cd8be451e31ddff97f8bfb/zotogevetezikapedom.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094598c12276---wokuzunaveguliwufud.pdfIn PDF document text
    • https://auto-rujo.com/images-editor/file/86010512682.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/7f0292440516b062e231457d1543b089/zozagevibekewepopakav.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ea611920d---kenafometewud.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/8a55a4f5edff76ee47a4335e1513ed45/77641089939.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/3899909439.pdfIn PDF document text
    • http://sdds.be/userfiles/file/90844345141.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/lerogolov.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c15dad3adec---33579860170.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/040d56ca04ae7ab6283b0d6293ae027e/21811425306.pdfIn PDF document text
    • http://ranahytta.com/ckfinder/userfiles/files/64463990656.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/107b3b80e06f3e7a661af104d3dc9c1d/50996612154.pdfIn PDF document text
    • http://stevis.cz/files/file/pewojirotonixumasopuwa.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/topexaxepisiruvobaxafomeb.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16077bab68f6bb---fuzafapeta.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/jqr2nhbbok35rrpq9ml9lgm9g5/46776309102.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/851af22a025c9accd6312ac13ed7c251/7326580489.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=gmt+time+with+secondsPDF 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_off00012d59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D59 18160 bytes
SHA-256: 170ad2f821e9bbe13e89210ed1af73d430e5dfc6ce090f03bc1b4d78e524ee55
font_01_sfnt_off00015ccf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15CCF 10452 bytes
SHA-256: a20cdb3764a98cca9b00c1dfee85e82bd8349cdc5845ba29ace20eee06c26d60
font_02_sfnt_off00017474.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17474 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1