Malicious PDF — malware analysis report

Static analysis result for SHA-256 85a775dabf28e8b4…

MALICIOUS

PDF

77.8 KB Created: 2021-09-03 19:00:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bef3f6ed9c981be3caf32acc000e74a0 SHA-1: e68063cea6a3eabeca67a5f4109e4339ad4e9c88 SHA-256: 85a775dabf28e8b486e0d650b0f71eaa857954846db0e0dc97da02a8f88c9889
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The file contains numerous embedded URLs that point to various domains, many of which are identified as compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://autoteam.in/ckfinder/userfiles/files/zugovibetuzuxeseselawes.pdf In PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a8b2ad717db---41375666818.pdfIn PDF document text
    • http://chetaomaynganhnhua.com/uploads/files/95368782799.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/82768082388.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/86790037667.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/l93gi2big3hc9t4bq3dvl417pt/60594631824.pdfIn PDF document text
    • http://porpora.info/imagenes/imagenes_contenidos///fijafu.pdfIn PDF document text
    • https://incense888.com/uploads//files/202108052355425071.pdfIn PDF document text
    • https://serviceservice.eu/userfiles/file/69536912841.pdfIn PDF document text
    • http://htygroup.com/upload/files/bizemuvizekev.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/94716228287.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd724f179f---11358479335.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/kizim.pdfIn PDF document text
    • http://cn-polylysine.com/d/files/61690943029.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/082fd54ed6eac419a22790e7ce547a9b/47797179358.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b4c374c77---xovif.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/tugetegafuvexurovibud.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/86936104126.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/3a6jijq3i00omapk5ingdh2qvj/jesota.pdfIn PDF document text
    • http://labsshop.com/d/files/48976060639.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/39bf7afe02cffed1edcfab9f40970a7e/12823084721.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/34710668720.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/12981781916.pdfIn PDF document text
    • http://karat-dobremiasto.pl/userfiles/file/86478206087.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=lumiere+blanche+cecilia+wang+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://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_off0000c926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC926 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE138 18684 bytes
SHA-256: d5f8008800bcb773a99a49dabb89e546471aad487ca635639100e8eafb1f5e5f
font_02_sfnt_off000110d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110D9 10964 bytes
SHA-256: 08a6cf223a17f9d7e05a921bdf69dfb6e618d033a25276a13ec23292e818453e