Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1e3a7750927e532…

MALICIOUS

PDF

81.7 KB Created: 2021-09-06 09:54:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c1dfd362ba44a8e1b5d9adeba54cff40 SHA-1: 9cf87e649861156c5c09913645c1fb3715d80ec1 SHA-256: a1e3a7750927e53242d52a05a2a59233402e575614b18b427fd9502069c65309
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The embedded URLs suggest an attempt to lead victims to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://doktor-okonski.pl/uploadimg/file/govalarixukiwemolotevi.pdf In PDF document text
    • https://childprotectionindia.com/lexcyberia/userfiles/files/lepobudizupukibuw.pdfIn PDF document text
    • http://ecandrychow.pl/Image/files/56858738156.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a94142b51---silalibol.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/59540738448.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/103cebc9b12704f97f873716dd667ec9/vetesugogafimi.pdfIn PDF document text
    • https://puntoagricoltura.it/file/sakinifaluji.pdfIn PDF document text
    • https://fo-prefectures.com/pages/files/nixivedojovojojuna.pdfIn PDF document text
    • http://agama-rc.com/upload/files/74247718383.pdfIn PDF document text
    • http://tplustech.com/images/ckeditor/files/5905303125.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612ead1a1eeca---deruxukulok.pdfIn PDF document text
    • https://proia.bg/userfiles/file/tibunezim.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/23041471773.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/38337448593.pdfIn PDF document text
    • http://camelliafb.com/uploads/files/202109021322317332.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f3b82029f---laluvuxavoruge.pdfIn PDF document text
    • http://tuyothuyluc.vn/webroot/img/files/5591303720.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608699fe73965---vimamopumu.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/03d4399e5c5dd2d715a789d378b12e34/sadunepapujulidu.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/putudinup.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/38135553778.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/5f341357ca349506fe034f5902d3acb1/ledisifupelamor.pdfIn PDF document text
    • http://itssilvertime.com/clients/2/24/24efe347a73a8ce028152bf895bc11a7/File/31389178989.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160875ecaadb64---jevudijawifipa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=story+in+cursive+writing+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_off0000db72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB72 17112 bytes
SHA-256: c2beb8e4ca14030ff8c486669ae6035ed7485689d51b2ad1d47334f52a95406d
font_01_sfnt_off00010776.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10776 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F8D 11028 bytes
SHA-256: 6255aeb631832b46555914fdb1b27b9e6777f2b08e77f083ca99dfc169100141