Malicious PDF — malware analysis report

Static analysis result for SHA-256 f99a58478e8859c8…

MALICIOUS

PDF

76.4 KB Created: 2021-09-13 21:35:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1bf9778ab5f1421b2cedebd7706bd923 SHA-1: 4ae465a0dab160b28ff07cdbc5d9bcb4fd5c3cef SHA-256: f99a58478e8859c8fd08c1e7f7fdf2b80986571d944e510e0ce2127d95d19276
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable hosting, and a heuristic identified it as a link farm. While no scripts were explicitly extracted, the presence of embedded URLs suggests an attempt to redirect users to potentially malicious sites, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://dptour.net/bot/ckfinder/uf/files/30496885739.pdf In PDF document text
    • http://qamsar.org/userfiles/files/namito.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c95b17bfb---23103961692.pdfIn PDF document text
    • https://mar3ol.com/Files/files/67450702054.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/16150429767.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/7556735156.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/62270116441.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/17646803606.pdfIn PDF document text
    • http://retrievers.su/ckfinder/userfiles/files/sowuwudixudikamikom.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/70592620937.pdfIn PDF document text
    • http://xn--2osv9pt2jfpt.com/uploadfiles/files/45174583857.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109050552398988.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/zuzizaxil.pdfIn PDF document text
    • http://321eastern-thailand.com/userfiles/files/gelasezeg.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/dirimeduvanoraxufiz.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/nepiladirigiva.pdfIn PDF document text
    • http://www.firstpages.eu/app/webroot/files/userfiles/files/44355385171.pdfIn PDF document text
    • https://needletherapy.eu/upload/file/vezixutaxowasoxal.pdfIn PDF document text
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/vexinariwefopafixe.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/72334891903.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/11698030747.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/24071172561.pdfIn PDF document text
    • http://johnmichaelharrisonlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/8281294551.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=free+call+recorder+for+iphone+indiaPDF 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_off0000c7e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7E4 10428 bytes
SHA-256: 6a9dbbe5e291ad31b3ce062f14f246c4bf06bac5d5899499b27254643ed00a9e
font_01_sfnt_off0000df4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f75f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75F 17024 bytes
SHA-256: f7fbee6bcc204026fe5bed3b2e68450767bba5aab33bd0c6bcd3b6268ba18b00