Malicious PDF — malware analysis report

Static analysis result for SHA-256 f15a767c1d5fede8…

MALICIOUS

PDF

92.9 KB Created: 2021-09-09 09:11:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8775048c4a764dc09a0912aa229af083 SHA-1: 31fe36f14b03334630b9039ffa25662a1c4a9e54 SHA-256: f15a767c1d5fede86e4d15a829cff25224c5151c86e7bbd106dcce2f6699946f
126 Risk Score

Malware Insights

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

The file was detected as a malicious PDF by ML classifiers and ClamAV. It contains numerous embedded URLs, many pointing to PDF files on various domains, suggesting a link farm or redirection scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a high number of distinct hosts with few links per host, characteristic of phishing or malware distribution sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://insureavisitor.com/userfiles/file/87586218653.pdf In PDF document text
    • http://dreamsurgerycn.com/ckupload/files/katavera.pdfIn PDF document text
    • https://tomorrowhubs.com/upload/users/files/99934559377.pdfIn PDF document text
    • http://uzmansporzeminkaplama.com/resimler/files/wenajib.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/gekudizurusep.pdfIn PDF document text
    • http://saopauloairporttransfers.com/ckfinder/userfiles/files/34293317075.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/94758045461.pdfIn PDF document text
    • https://srccaa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/dezogapez.pdfIn PDF document text
    • http://farashimirooz.com/files/48997809089.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/dijolafibe.pdfIn PDF document text
    • http://atsolution.org/userfiles/file/20210909072153683758545.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/161337088937b2---dusuburikagedosinulaxobow.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/safokogugisajavufibezan.pdfIn PDF document text
    • http://basaritarim.net/admin/editor_resim/file/45419128474.pdfIn PDF document text
    • http://achilleferolla.it/userfiles/files/65671678572.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/xujojumuzefaw.pdfIn PDF document text
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/mujuzafezesigadepok.pdfIn PDF document text
    • http://szyuangang.com/UserFiles/file///68219579111.pdfIn PDF document text
    • https://www.pharmawell.eu/ckfinder/userfiles/files/jalividobukekifiv.pdfIn PDF document text
    • http://www.ciesol.es/ckfinder/userfiles/files/rebujase.pdfIn PDF document text
    • http://pincesorvarshop.hu/editor_up/xipidalobamisapidod.pdfIn PDF document text
    • http://hanlacsclub.com/ckupload/files/jipek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=what+is+google+appPDF 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_off00010a18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001222f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1222F 10320 bytes
SHA-256: dd6a2ca139f64666244de92a82664dd0e6d6b5152c792856a0cc6ee8c5571ab7
font_02_sfnt_off0001399e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1399E 17140 bytes
SHA-256: 56f2d7753452f3268c913ea7c230cadd75b1ae0172f944eab3f4b3f40f16063e