Malicious PDF — malware analysis report

Static analysis result for SHA-256 b28245f66340eac7…

MALICIOUS

PDF

81.5 KB Created: 2021-08-15 23:55:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 37671953f9b9cb74769ade0db0db7321 SHA-1: 26f922fc0327e25a85216f0b0d7e1908defbdd50 SHA-256: b28245f66340eac7052bc9cfdd6cb27223b5b6b6933a620d6d47fbbf605f61a9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with several pointing to compromised WordPress upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or credential harvesting via the linked sites. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://www.childofafrica.org/media/userfiles/file/31757972321.pdf In PDF document text
    • http://dailygiasi.com/uploads/userfiles/file/7259870632.pdfIn PDF document text
    • http://sevenseahotel.com/uploads/images/files/lerowilemixexuwiwavulur.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/fobejaxajabopexe.pdfIn PDF document text
    • http://saaretravel.ee/images/file/bativorexi.pdfIn PDF document text
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/552afcb11ea3a5c5a59a0e4ae4e276cb/73300796296.pdfIn PDF document text
    • https://www.sacda.org/wp-content/plugins/super-forms/uploads/php/files/tc8li0e7bk9r702c6t24a3h5h4/fofutodupade.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc422a10a5---tunife.pdfIn PDF document text
    • https://himalmanpower.com/ckfinder/userfiles/files/reson.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/nosudewezozupotezubiraku.pdfIn PDF document text
    • http://kiuanai.com/userfiles/file/gimowokimuxul.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a88c182f69e---9315795017.pdfIn PDF document text
    • http://goref.ru/files/file/58960414865.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/0653404c8c88452f91969472a15322b6/81948739235.pdfIn PDF document text
    • https://soechi.id/userfiles/file/feriwabix.pdfIn PDF document text
    • https://atl-50.com/files/file/koxonito.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/bazizufutevizedura.pdfIn PDF document text
    • http://wadsoda.com/UserFiles/File/7698016172.pdfIn PDF document text
    • https://ambient-interier.cz/files/files/27468516317.pdfIn PDF document text
    • https://advertisementnepal.com/ckfinder/userfiles/files/zagigekizafosasifadede.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609717e527058---76977680276.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/osc536gpkp3gvg1njh24in0u95/7492401252.pdfIn PDF document text
    • http://baugeraeteverleih.de/benutzerdateien/goxigedekinasap.pdfIn PDF document text
    • https://network-italia.com/file/kasoligugitojisexuwuteg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=bellsouth.net+email+sign+in+pagePDF 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_off0000da93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA93 10816 bytes
SHA-256: 5dacdea4b094ec15664d4452cae68a372ca71237001dd5897f5b6c8a2d7ee0d2
font_01_sfnt_off0000f35a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF35A 16868 bytes
SHA-256: 62a3445915f50260cc84f79938ee17796a81bf06bc7236492daf315ef1107ed9
font_02_sfnt_off00011f18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1