Malicious PDF — malware analysis report

Static analysis result for SHA-256 54da23d7111b3205…

MALICIOUS

PDF

68.7 KB Created: 2021-09-25 21:55:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3d02b188d6d57e1129b41b48703d079f SHA-1: bdd2d7c7c06d4fc94e17d7685841a5c8dcc44926 SHA-256: 54da23d7111b3205bdeb6331a016d0d2800a2fe035378c027eea4abec52fa2de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://coretry.ru/uplcv?utm_term=number+talks+pdf PDF link annotation
    • http://zhouzhuanx.com/v15/Upload/file/20219244446852.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/87484000753.pdfIn PDF document text
    • https://fanaf.org/article_ressources/file/duzizikavulowizedasut.pdfIn PDF document text
    • https://shiprapublication.com/uniformkontakt/userfiles/image/files/wakidelugupor.pdfIn PDF document text
    • https://stillwaiting.org/userfiles/file/wadogokex.pdfIn PDF document text
    • https://renewone.de/files/19971704592.pdfIn PDF document text
    • http://ubytovani-budejovice.cz/picture/vtextu/file/govezapuwomubagavisazatez.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614c0197c5606---lenemutami.pdfIn PDF document text
    • http://foodchemsino.com/d/files/41062732171.pdfIn PDF document text
    • http://defhjdr.friend-match.com/upload/files/8036070502.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/1b306dea64ee44304e3c4e421dab294d/76584930195.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5f34e57c8---peditifujonudo.pdfIn PDF document text
    • https://anandamsanyal.com/userfiles/file/jexan.pdfIn PDF document text
    • http://larben.cz/media/images/upload/file/falare.pdfIn PDF document text
    • https://taperagi.com/contents/files/21867201888.pdfIn PDF document text
    • https://get-insurance.in/ckfinder/userfiles/files/47865112141.pdfIn PDF document text
    • http://nuitsdartistes.eu/images/file/64233322056.pdfIn PDF document text
    • https://hotelindigha.com/FCKeditor/file/waxidetubodomi.pdfIn PDF document text
    • http://clingac.com/d/files/sawolofovibifexovekovulux.pdfIn PDF document text
    • https://landtop.com/filespath/files/20210907001055.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///zowabopokovatoz.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/156a276688c657838b91c6175cb750c7/46389220480.pdfIn PDF document text
    • 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_off0000afe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7FE 10652 bytes
SHA-256: 5dc50ce53a60accfa420e6083f00d6a12ad75222d2b5a1792a299c52d65e8b5d
font_02_sfnt_off0000e033.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE033 14828 bytes
SHA-256: 56274c317a1d56549e6e0c410f84bc4905e6adeb9935dc9fac36630fe358d0de