Malicious PDF — malware analysis report

Static analysis result for SHA-256 b90f311f53d2d871…

MALICIOUS

PDF

79.9 KB Created: 2021-09-13 09:30:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6aa0ca17917f340805973895f957566e SHA-1: f92c643d3c0bad164e8b09818902e106669e1104 SHA-256: b90f311f53d2d871125938406e15f9281874a5738d17488d5398c991b077ac56
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to disposable hosting or are part of a link farm, suggesting a phishing or malware distribution scheme. The presence of external URIs and the overall structure strongly suggest this PDF is intended to lure users to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 https://krisoc.ru/uplcv?utm_term=highest+graphics+game+on+android PDF link annotation
    • https://siriusdynamics.com/assets/uploads/files/57038799562.pdfIn PDF document text
    • http://www.stemcellhairclinic.com/files/files/xanawekubutekakojop.pdfIn PDF document text
    • http://skontrolsengineering.com/file_media/file_image/file/kevaz.pdfIn PDF document text
    • https://rtvpuls.com/ckfinder/userfiles/files/490481688.pdfIn PDF document text
    • https://dukeofmarshall.com/ckfinder/userfiles/files/58404381634.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/lorisegu.pdfIn PDF document text
    • http://dytac.hk/userfiles/gebowukiki.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/89286303378.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/wejibuvebagadu.pdfIn PDF document text
    • https://malabarmail.com/ckfinder/userfiles/files/69663605615.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/1721761931.pdfIn PDF document text
    • http://chiesamadremarsala.eu/userfiles/files/nofaluxesagamibixow.pdfIn PDF document text
    • http://2m-m.eu/userfiles/files/zoxepedemik.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/fewatagame.pdfIn PDF document text
    • http://ambulatorioveterinarioilprato.eu/userfiles/files/rafusaxebelorumugulu.pdfIn PDF document text
    • https://aparcaderoshaddaichile.cl/uploads/images/files/70396329026.pdfIn PDF document text
    • http://avsa.org/sites/default/files/images/files/sogagikebigab.pdfIn PDF document text
    • https://banerjeetourspecial.in/ckfinder/userfiles/files/revibatewikovuwof.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/dutujofujapurojepexiwi.pdfIn PDF document text
    • http://fohow77.ru/upload/file/xaravitimorez.pdfIn PDF document text
    • https://perfecthospital.org/ckfinder/userfiles/files/31799284005.pdfIn PDF document text
    • https://pmsp-me.com/userfiles/files/41812335726.pdfIn PDF document text
    • https://primer-spb.ru/files/files/nirakowezuvumujup.pdfIn PDF document text
    • https://vialivonica.eu/userfiles/files/zipalutagu.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2c1c950df---58405595164.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_off0000d591.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD591 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eda8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA8 10904 bytes
SHA-256: 7f08fb3e842347ac1d50040e90abae4d27dddbcd438d90cd62912693389a341b
font_02_sfnt_off00010674.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10674 17020 bytes
SHA-256: 9c96d0b63b17df233a7b767b9be1144a60e6aa08258e7dcfafe530a282d4a54d