Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec955d5fd0569fb6…

MALICIOUS

PDF

80.0 KB Created: 2021-09-18 13:03:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bb2f1da848d30287aad0a135082c71e7 SHA-1: 0a857e3fa300ddffc99a2188981265a2de4f243b SHA-256: ec955d5fd0569fb6ef0caa4de7487bc72f0badee770851c708efbcce91dcb665
164 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, pointing to compromised CMS uploads and disposable hosting, likely to host or distribute malware. The presence of a 'download button' lure further supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8014

Heuristics 7

  • 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.
  • 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 https://acconpriti.com/ckfinder/userfiles/files/segirofuduk.pdf In PDF document text
    • https://relans-nn.ru/images/docs/file/21804978789.pdfIn PDF document text
    • https://at-studio.tw/app/webroot/userfiles/files/20210901_110717.pdfIn PDF document text
    • http://ahdjcm.com/upload/files/fegilufisaxizepadomakale.pdfIn PDF document text
    • https://sibiucuratenie.ro/fckeditor/userfiles/file/susezafonir.pdfIn PDF document text
    • https://meganimal.pt/site/upload/file/mewinika.pdfIn PDF document text
    • https://anandalaya.in/resources/file/pabifudawabusijomiz.pdfIn PDF document text
    • http://kraski-chernila.ru/resources/file/lapelewibipakiwurixoku.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/gemurazesotiwop.pdfIn PDF document text
    • http://lovepetclinics.com/file_media/file_image/file/jatiwupemogeve.pdfIn PDF document text
    • https://soi.icami.mx/ckfinder/userfiles/files/nunurimavosisotufuput.pdfIn PDF document text
    • https://mamo-tato.ro/userfiles/file/75312308067.pdfIn PDF document text
    • https://bacninhonline.com/webroot/img/files/95617197539.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/b1505e0118b830070b5bd103af6dd1ce/palaremezomudiguxinoda.pdfIn PDF document text
    • http://phyllisrubensteinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/55678884814.pdfIn PDF document text
    • http://optimaglobal.net/ckupload/files/18399382930.pdfIn PDF document text
    • http://ccspatti.org/userfiles/file/xikuxadufutusezajet.pdfIn PDF document text
    • https://cribpointonline.org/cribpointonline/userimages/file/93122402448.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613428ce14145---zagaxe.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/9bfd9db5ee768d28afd4045953fbc685/97731897835.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613340d49fe73---75566619958.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/87870188144.pdfIn PDF document text
    • http://silesiacapital.eu/data/file/17632807489.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=download+hungry+dragon+apkPDF link annotation
    • 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_off0000db3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB3D 17948 bytes
SHA-256: 111da3fdd431686efa8da15b381eb61604f444062fd5b2b1d955a8d607d388fa
font_01_sfnt_off00010a04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001221b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1221B 10576 bytes
SHA-256: 7acccf489e74110ef00f77c33810a609e30f9956b40945330926a112da1475f4