Malicious PDF — malware analysis report

Static analysis result for SHA-256 c12763b5b28483e8…

MALICIOUS

PDF

85.0 KB Created: 2021-10-06 10:25:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 5e133d6fbdc05e24dcef322d0c367309 SHA-1: 34c598178ab06b9c9bcf0c848511000f5fb01f0f SHA-256: c12763b5b28483e88f536e3824b2717eca2cf81b33b1869dd571b8035d1bbed7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to PDF files on distinct hosts, indicating a link farm designed to distribute malicious content or phish users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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 http://torgoborud.org/images/file/nuxig.pdf In PDF document text
    • https://luckysurface.itweald.com/uploads/files/614692be715bf.pdfIn PDF document text
    • http://yasaitogo.com/uploads/files/48406446615.pdfIn PDF document text
    • https://solucionaesp.com/ckfinder/userfiles/files/tusazezomosiluwipofori.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615bf8fde39da---44314175475.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/20854733562.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615581cf70174---vowominowadatidopi.pdfIn PDF document text
    • http://graczeonline.pl/userfiles/file/kakuboligurubopadasuzutu.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/56982874711.pdfIn PDF document text
    • https://riminabda.sk/userfiles/file/49367457907.pdfIn PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/32664813982.pdfIn PDF document text
    • http://xingzhongjing.com/userfiles/file/20211006054347_1504591118.pdfIn PDF document text
    • http://icsbc.ru/fuploader/file/4431827687.pdfIn PDF document text
    • https://piataafacerilor.ro/app/webroot/files/userfiles/files/95817953311.pdfIn PDF document text
    • http://cy2hand.com/userfiles/88136598955.pdfIn PDF document text
    • https://virtrade.gr/userfiles_lybo/file/95557244259.pdfIn PDF document text
    • https://iwanbim.com/userfiles/files/jupem.pdfIn PDF document text
    • https://garnizone.com/userfiles/file/89717294449.pdfIn PDF document text
    • http://infoegrafica.com/userfiles/files/26005356341.pdfIn PDF document text
    • http://belst.by/upload/file/dasukixogavewovotokola.pdfIn PDF document text
    • https://alpasol.e-giant.net/upload/files/80503751766.pdfIn PDF document text
    • https://kultmotor.hu/images/files/jewirufofetusinulura.pdfIn PDF document text
    • http://abpjse.news-read.com/upload/files/29446401336.pdfIn PDF document text
    • https://yauspeshen.com/ckfinder/userfiles/files/sikufefafezisesigememusa.pdfIn PDF document text
    • http://ateliergermain.club/sites/default/files/file/mubivaguvegedepoburapum.pdfIn PDF document text
    • http://capableapp.com/uploads/files/36144003580.pdfIn PDF document text
    • https://prestinieurope.com/userfiles/files/fuleguvodan.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=are+website+names+italicizedPDF 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_off0000e490.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE490 18476 bytes
SHA-256: f8a924f9edd8ff5b6578a912611f19d2bafa5e6dbeb34526291a5ab34bcae9b6
font_01_sfnt_off00011553.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11553 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D6A 10676 bytes
SHA-256: c63a68c4a5433e564f2dcc1b2be6d7802858f9e2d1a13c3ef2b791655a96d9e1