Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dffce435c081076…

MALICIOUS

PDF

68.1 KB Created: 2021-06-22 20:47:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 21e3cbe9ddcbf5351ffd47bbd6d25633 SHA-1: 08862cc9f3a246f8bb2c77668f0a13000079ede2 SHA-256: 8dffce435c08107638f819f632d1e768e7c202a03be5ac5f04f963abc555ec07
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, designed to redirect users. The presence of embedded URLs and the PDF structure suggest an attempt to lure users to external malicious content, consistent with phishing or malware delivery tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://t2sc.me/userfiles/towovekisiwe.pdf In PDF document text
    • http://etabetasurvey.com/userfiles/files/musaror.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/780ddf40d83bdf2a55b8af5c6c1edf36/82061090812.pdfIn PDF document text
    • https://avela.md/userfiles/file/33464046277.pdfIn PDF document text
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160baf1a1d2473---43460879143.pdfIn PDF document text
    • https://oklogistic.lv/upload/file/vesapabile.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/pojorususofixi.pdfIn PDF document text
    • http://logisticsnetworks.net/ckfinder/userfiles/files/belosokapakogusejogipewe.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/3u9tck890ga1s6vdsfq50ffio0/menanuxenedugoxapedosita.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609e31ef33351---xulozubarebev.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609697c82232f---silelufebopenagikokamowo.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/turelufedopezibubalu.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c65e1b912b3---52134268476.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160877c2f7e807---bapirawewoxezakemorajemi.pdfIn PDF document text
    • http://cnex.cc/images/blog//file/budivotuxusolup.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=cafe+solo+andrea+ferrari+pdfPDF 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://scripts.sil.org/OFLIn 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_off0000b54d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB54D 4940 bytes
SHA-256: 6db71700c195e49896976be519f5976f65cfca2b77f553536726ff891bc701d0
font_01_sfnt_off0000c625.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC625 11832 bytes
SHA-256: bbc935e0cfc0d1be1537204ce24c3a6e41d55c0291efc99a90a599bdde745f46
font_02_sfnt_off0000ec76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC76 16140 bytes
SHA-256: 159427b32ed66bfbde86def5e6c2992bde67dfb25400c4000a37c9b59b949b61