Malicious PDF — malware analysis report

Static analysis result for SHA-256 904ffc76864aa827…

MALICIOUS

PDF

69.9 KB Created: 2021-09-30 23:34:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 31b6f18016794f55eeb6de0c70d729d8 SHA-1: 32c503dfe8ae31c4af551dbdd267634dc3a7c2d1 SHA-256: 904ffc76864aa8277ed31cf7751f0f45aaccbcb2cdfe83a006ee54e93b8f8d66
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous domains, many of which host PDFs. Heuristics indicate these links are on compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users into downloading further malicious content or phishing for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/k0ndg9hkn25310paho87i391h3/sejamawugirata.pdf In PDF document text
    • https://stijsr.com/userfiles/file/xoginu.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/jatevilixuromejuvodozal.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/70510307514.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/82684967374.pdfIn PDF document text
    • http://grotech.in/userfiles/file/51447713117.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/99200319314.pdfIn PDF document text
    • https://www.domaine-de-la-ferme.fr/ckfinder/userfiles/files/24514489608.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/fepubamobewunavet.pdfIn PDF document text
    • http://www.trackls.com/application/ckeditor/ckfinder/userfiles/files/82838595745.pdfIn PDF document text
    • https://machnik.net/ckfinder/userfiles/files/fupizomesufifef.pdfIn PDF document text
    • http://safarang.com/basefile/files/rezatidavudi.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/2da6d4600e86ddd9634abb322c963c63/24233014451.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/2117129106.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147ab03ccb5b---mujotunirozanuxagisarano.pdfIn PDF document text
    • http://balogmihaly.hu/UserFiles/file/36124377411.pdfIn PDF document text
    • https://fibaquitaine.fr/cebatrama/userfiles/files/96962742849.pdfIn PDF document text
    • http://congseng.com/uploadfile/files/26314949116.pdfIn PDF document text
    • http://www.rodnolespropertymanagement.com/siteuploads/editorimg/file/zazuzarut.pdfIn PDF document text
    • http://naso10.com/userData/board/file/33216985618.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/44739881320.pdfIn PDF document text
    • http://web-news.eu/www/pkpar/userfiles/file/kemomuxomijavulerutolon.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=american+english+file+3+teacher%27s+book+pdf+free+downloadPDF 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_off0000b12a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB12A 14828 bytes
SHA-256: 712ec1c8a339099873b21f35dc34efa704fc971ca011cb470d2943e975081493
font_01_sfnt_off0000d66a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD66A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE81 11572 bytes
SHA-256: 8fdede8575d8398a231ed995ab786f020bbd84485dec8e65392c13b179f05fa1