Malicious PDF — malware analysis report

Static analysis result for SHA-256 f83d3045e159a982…

MALICIOUS

PDF

83.2 KB Created: 2021-09-23 05:47:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7d3d2ea4f27eb5d295349e208e9af9f2 SHA-1: c062a4d1ae52f5d96f3406eccb56865f27c557ad SHA-256: f83d3045e159a9828335499020355db5d3023a5f7f26d664eaa0fe6e11e531d2
126 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics and a machine learning classifier as malicious, specifically identified as a phishing trojan by ClamAV. It contains numerous embedded URLs pointing to disposable domains, suggesting a link farm designed to lure users to malicious content. The document body was unreadable, but the overall structure and URL analysis strongly indicate a phishing attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://deesudcoolingtower.com/userfiles/file/45913530872.pdf In PDF document text
    • http://chayka-svg.ru/files/4559250342.pdfIn PDF document text
    • http://citranco.com/users/files/kuvawukamevofafuzorilem.pdfIn PDF document text
    • http://brava-ekb.ru/userfiles/file/95821854313.pdfIn PDF document text
    • https://paymentor.nl/uploads/file/49761632487.pdfIn PDF document text
    • http://seowonbattery.com/files/fckeditor/file/1146794557613ae002cf941.pdfIn PDF document text
    • https://matteagianotti.ch/userfiles/files/22836220968.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/352217512.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/wozolaz.pdfIn PDF document text
    • http://satcomlink.com/userData/board/file/22868914428.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/47984794729.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/podefazorogupoli.pdfIn PDF document text
    • http://tubesealer.com/uploaded/file/180336661161481d398b32d.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/7523549412.pdfIn PDF document text
    • http://neowork-rh.com/userfiles/file/2738019855.pdfIn PDF document text
    • https://edex.co/userfiles/files/14763239306.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/4177686223.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/29328266170.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/dewamovoluzasu.pdfIn PDF document text
    • http://msiutilities.biz/documents/3922264294.pdfIn PDF document text
    • http://chelseafoodmart.com/uploads/files/28703750078.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/50317384250.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=app+games+for+android+phonePDF 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_off0000e11b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f92d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF92D 17604 bytes
SHA-256: 832af17f74204ea0b08c2a6fcf41742ed974d63954c8bc69974c5534389c6fef
font_02_sfnt_off000126ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126FF 10784 bytes
SHA-256: f4457b1f89101017f14839734caa406d687f17434cd26bfda5d2efdca5528836