Malicious PDF — malware analysis report

Static analysis result for SHA-256 ccd8634d72286d24…

MALICIOUS

PDF

81.5 KB Created: 2021-09-12 18:53:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 98131d50221c1c6bd508ec21349851cf SHA-1: 9cd39bb0ae3f7dd304124b95dfa05b48aabc9a81 SHA-256: ccd8634d72286d24f8aed6bad53a3585f18a6e79a99d89e40148e1a3beadd41c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically a phishing trojan. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to obscure the ultimate destination. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 7

  • 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.
  • 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://vandervalk.reviews/app/webroot/files/userfiles/files/22283406056.pdf In PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/07352e67f2cbdd1e1cdf7a15de39c565/15562258720.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/f64778fbf00a6153feffbcf1c6d0cddf/wigekosafenegunivoxuramuv.pdfIn PDF document text
    • http://nuitsdartistes.eu/images/file/bigolamexoxekojog.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/madutojozogosa.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613685cd2f57d---96395232304.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/61193986064.pdfIn PDF document text
    • https://kimcert.org/E/file/nupepulifolizawozusojom.pdfIn PDF document text
    • https://goldenlinejsc.com/userfiles/file/tobuwuvizoxajel.pdfIn PDF document text
    • http://espaciocultivarte.com/ckfinder/userfiles/files/dapaparojuvevuniwulufane.pdfIn PDF document text
    • https://molecult.metallo-tests.ch/sites/web/upload/files/rekokexetuzefovazofunem.pdfIn PDF document text
    • https://www.casestilistas.es/ckfinder/userfiles/files/rivurugudiwoze.pdfIn PDF document text
    • http://hyundai-dongdo.vn/images/files/91996341707.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161356cdbc700d---jelefanala.pdfIn PDF document text
    • https://batikatravels.com/userfiles/file/fuzuragenavoxafid.pdfIn PDF document text
    • http://hcbarrett.com/user_area/file/66588708286.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396930bf999---82068484747.pdfIn PDF document text
    • http://mylivediamondinventory.com/uploads/files/lodomuvixopujowesokaxexud.pdfIn PDF document text
    • http://e-park.es/img/uploads/files/72257343219.pdfIn PDF document text
    • http://live-net.it/file/vesaxetufa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=hopeless+land+unlimited+moneyPDF 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_off0000d99e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD99E 17976 bytes
SHA-256: 29173711fcaff0437bc1e7a2fc3f68fcf65c4cf519c5203a44603d132f6e4271
font_01_sfnt_off00010853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10853 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001206a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1206A 10660 bytes
SHA-256: 5a28be3d877253a9289afa40bdaf57bbd9fbdcc2221279a09f7df1cab4dc6a3d