Malicious PDF — malware analysis report

Static analysis result for SHA-256 42f47307c374fc58…

MALICIOUS

PDF

71.1 KB Created: 2021-09-12 07:27:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 90c6bfa8100a746817e58d93774a9de9 SHA-1: 12d7e24567f1a7fbbbc12d73afa82fe90173950a SHA-256: 42f47307c374fc58e6171be307b141851be1166532d7a62cd8fe2788a6df8e83
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of numerous unknown reputation URLs suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://cke.hk/userfiles/giralof.pdf In PDF document text
    • https://lockerova.eu/admin/upload/documents/lemiga.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/pemewulerifige.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134051b0190e---84966730163.pdfIn PDF document text
    • https://endobible.com/userfiles/file/tokigesovonelenitad.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/nupudolokunibuto.pdfIn PDF document text
    • https://ddtoyz.com/ckfinder/userfiles/files/wologi.pdfIn PDF document text
    • https://tutorlookup.com/ckeditor/ckfinder/userfiles/files/61078078033.pdfIn PDF document text
    • https://malinaionescu.ro/userfiles/file/54508790737.pdfIn PDF document text
    • http://sacoorhealth.pt/site/upload/file/89473032116.pdfIn PDF document text
    • http://zzweien.com/d/files/perasapizu.pdfIn PDF document text
    • https://istruttorecinofilo.it/userfiles/file/pomalegogazota.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/40367634231.pdfIn PDF document text
    • https://5uempat.com/contents/files/marewamubunat.pdfIn PDF document text
    • https://academiapreprod.riportico.com/userfiles/files/20076840687.pdfIn PDF document text
    • https://tekmaker.com/upload/files/54693701510.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd2f182c69---jowezifasafogozux.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/gusupuxupunu.pdfIn PDF document text
    • http://vvk-wiedermann.at/userfiles/file/gimivirariwazebirimebagud.pdfIn PDF document text
    • http://nghieuphong.com/upload/files/daruneloporokusilotafawu.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f7bce9f28---gevidoxotozofipaxotalomol.pdfIn PDF document text
    • https://karlholmbygg.se/UserFiles/files/vimenolaxizimasa.pdfIn PDF document text
    • http://langyupharm.com/upload/files/bofunevinawejukefoketuku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=php+to+pdf+converter+for+androidPDF 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_off0000b3d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3D5 10572 bytes
SHA-256: bda4213162a80c40bfe798af5479134bfa08735555be2267dd64c71d0fb0223f
font_01_sfnt_off0000cbe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE6 16628 bytes
SHA-256: 1adb8569d7151c5c4f8e06d7d01a62e4d3015b7082df2dbd0d2615c4d6648282
font_02_sfnt_off0000f6be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1