Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd7b33c55e064569…

MALICIOUS

PDF

83.5 KB Created: 2021-09-02 06:00:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d5574c27da51a1795891ae3ebabe04de SHA-1: 68dfd2ecec9e57eb6abc5ec7a861a3903fdd9d43 SHA-256: dd7b33c55e064569148fff8e98418bcdc335b0d80384dfeac8dbfe8c15a15048
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is often used to download and execute additional malicious content. The PDF also features a link farm pointing to compromised WordPress upload storage and other disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://thucphamtruongxanh.com/Upload/files/99636129321.pdf In PDF document text
    • http://nessium.fr/userfiles/file/femirixexiviri.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/89722478934.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/tozogonuvebemeb.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160be4781b59a7---61939874901.pdfIn PDF document text
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/c19c353775d9d754c37263a1ae64cc4b/92255217273.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9bd410b61---zurekefolonokotijuda.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/4077ab27b431c26659eb694f46fc54cb/50554543924.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/panakajibufomigo.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ogn5sb2mjqamfgv823d00fp2m3/24523170544.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/fovizegoli.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210829_3D4B35D6A9E03852.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d6fb36ca9---94634552818.pdfIn PDF document text
    • https://www.adilaltinsoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d25869c4f6---77525399520.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/pepurugugurufadek.pdfIn PDF document text
    • https://sysyanginguvenlik.com/uploads/files/rafezaguja.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bd861392c79---51300028981.pdfIn PDF document text
    • http://elmbbq.com/uploads/files/84104514643.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f08e56e19---72371662215.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085268a337ed---69420401347.pdfIn PDF document text
    • http://diamond6ranch.com/userfiles/file/verubifezixofivifalezono.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/oas1nj9cre04ug4jaahe8efh23/62873422058.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=facts+about+traumaPDF link annotation
    • https://mediacentre.aerlingus.com/js/ckfinder/userfiles/files/dopupa.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_off0000e088.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE088 10236 bytes
SHA-256: 1ec010807034dfcf5ac414cdafae912d759d527857812a3b54e039b7ff055fa8
font_01_sfnt_off0000f79d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010faf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FAF 18508 bytes
SHA-256: 53ebc15159fb5eb540ebb49017d18f0cfbb59630d234511a0b2f166e97e161ed