Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c84adbbd7aa392b…

MALICIOUS

PDF

89.1 KB Created: 2021-09-11 02:50:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2766f75939cee03a552ddb2d9b4768a6 SHA-1: 438bbc24de79fad2e8e0a3810eb4882425beb097 SHA-256: 8c84adbbd7aa392b92f4f643f5bd754c5149abb0170d6155566baf06a0068214
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or are part of a link farm designed to obscure the final destination. ClamAV and an ML classifier flagged this PDF as malicious, specifically as a phishing trojan. The presence of a link farm and compromised hosting suggests an attempt to lure users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://louisamerino.com/userfiles/file/18900846951.pdf In PDF document text
    • http://candientu24h.vn/webroot/img/files/82787431447.pdfIn PDF document text
    • https://swagath.co/new/ckfinder/userfiles/files/kotadiwu.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/93886743139.pdfIn PDF document text
    • http://www.cottagegrad.ru/files/file/63269825161.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc4660a18b---72735337440.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/najonurusapuvenumikokos.pdfIn PDF document text
    • https://southernwashpros.com/nbloom/fckuploads/file/75359249474.pdfIn PDF document text
    • http://china-miyaco.com/img/file/202196161217.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/13790163828.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/sefatupori.pdfIn PDF document text
    • http://zbirozskepodzamci.cz/userfiles/44545940303.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/rf3mldr7bpd9ti03bcfaol6t40/16457423305.pdfIn PDF document text
    • http://recrute.fr/files/files/66485280683.pdfIn PDF document text
    • https://samsungklimamodelleri.com/upload/ckfinder/files/49901950752.pdfIn PDF document text
    • http://maimungkorn.com/UserFiles/file/21785223522.pdfIn PDF document text
    • https://thietbivesinhsonhoa.com/webroot/img/files/34032587554.pdfIn PDF document text
    • https://chataigne-cevennes.fr/imgs/files/11784584339.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/bawaf.pdfIn PDF document text
    • http://cppzone.ru/users/blogs/file/losufipukonubaxewabap.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393582da4b6---89442888148.pdfIn PDF document text
    • https://gencerenerji.com/resimler/files/68325435474.pdfIn PDF document text
    • http://trubaopt.ru/content/file/maletalavugofenefa.pdfIn PDF document text
    • http://mlead.net/images/e/file/noxapolomag.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/97807477218.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=top+5+best+games+2021PDF 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_off0000f564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF564 10784 bytes
SHA-256: 323fdfb375866b8dbd24f21d538ac2919531e5583d08726b69c16132dc55562f
font_01_sfnt_off00010e30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E30 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012642.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12642 18588 bytes
SHA-256: 573502beeda2252b60870df6b29c314bb47fcb568bc8423481e0ec58d069c458