Malicious PDF — malware analysis report

Static analysis result for SHA-256 44ff3f8b4e306e26…

MALICIOUS

PDF

78.0 KB Created: 2021-06-25 09:01:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 8c6e2078817fef726e2616aa5b84d21e SHA-1: e873acd85e0ec688899a394ac42684d2637dc502 SHA-256: 44ff3f8b4e306e26010d4ed4208ec6f4d6b1f7d037a2f789bc3ff09b8fa1d958
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS uploads or appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were directly extracted, the structure and embedded URLs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/02399385a79a351eed3ef2e2d0d5df40/45013204053.pdf In PDF document text
    • https://coil.hk/upload/files/92109578418.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608d266c2a243---92787218503.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/8f325efdd14e506a3f1b70be39cd2ef8/bujupufupaji.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b416d7df1e5---vokexemulujebe.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160719a57e2536---zapefi.pdfIn PDF document text
    • http://naasschoolofmotoring.ie/fckeditor/userfiles/file/wobujizanejosekejez.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202105021654006936.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/wonuvirabajexorojomagas.pdfIn PDF document text
    • https://www.autodepotperformancegroup.ca/wp-content/plugins/super-forms/uploads/php/files/bl9jrj0e4oj7pfi8ak59n4klh4/nujosesuzavusi.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160afba5832dff---40253686135.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/nepewiwebofonelomo.pdfIn PDF document text
    • http://jhferry.com/data/fckeditor/file/%5C/32439301042.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/s1tn7rd216mg1rkk99amdk5le5/fanumiwo.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/4utttffqokc0at89hunf6bqfb6/59609446003.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/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=pdf+editor+software+free+download+filehippoPDF 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_off0000dece.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDECE 5220 bytes
SHA-256: e3af8a2ecd0684c4cff766f6ff8362c1e05ea832dda5587e9aaa8a499b9863d0
font_01_sfnt_off0000f0a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A1 10836 bytes
SHA-256: 33976cd75227781c5d940f63b3390dba8dd967a4c945266f48fd946b53f56fe1
font_02_sfnt_off0001154f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1154F 16160 bytes
SHA-256: 5446d8693f472ebe56539db1294e6b993809411a69d567c9d8907fa578c39aa0