Malicious PDF — malware analysis report

Static analysis result for SHA-256 863597f4dd24e565…

MALICIOUS

PDF

73.4 KB Created: 2021-09-20 13:47:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 01ba141bed5ed9a6d51f8fa686b9e129 SHA-1: 0374564ef6dc3f902d77bd3c110ffd49d181fbf7 SHA-256: 863597f4dd24e5656b233e80f3e9845ef2b4aa5d002805c61c36be1e3cad0a88
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains identified as link farms or potentially compromised CMS uploads. The ML classifier and ClamAV heuristic strongly indicate maliciousness, classifying it as a phishing or trojan PDF. The primary function appears to be redirecting users to external sites, likely for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://phoiinnhiet.com/images/uploads/files/82098546973.pdf In PDF document text
    • http://mynigaoe.com/upload/file/20210911030159.pdfIn PDF document text
    • https://monographie.com/ckfinder/userfiles/files/19182309503.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/42090008841.pdfIn PDF document text
    • http://mnarch.it/userfiles/files/29116843728.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/20821286531.pdfIn PDF document text
    • https://razredna-nastava.net/files/fubuxa.pdfIn PDF document text
    • http://infas.cz/images/wiswig/file/99869266891.pdfIn PDF document text
    • http://surausa.com/uploads/files/vowinonudigubag.pdfIn PDF document text
    • https://knoxvilleremembers.com/media/supojijivubed.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/161370c564fa5b---15424327869.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1631815971.pdfIn PDF document text
    • https://fanaf.com/article_ressources/file/vakawimuzituni.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/18302093404.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/mebisetezewopujetuxi.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614109e12389b---21702942892.pdfIn PDF document text
    • https://brune-schmuckwerk.de/ckfinder/userfiles/files/71828284514.pdfIn PDF document text
    • http://33podarka.ru/pictures/files/riburewogilaxunu.pdfIn PDF document text
    • http://micruts.org/userfiles/file/xibokejenasasoxiwem.pdfIn PDF document text
    • http://kamerton.nl/clientfiles/75866136165.pdfIn PDF document text
    • https://tamphuctriland.vn/upload/files/827745059.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161474e5e47346---dilikida.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=structure+of+embryo+sac+in+plantsPDF 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_off0000bb80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD397 11068 bytes
SHA-256: f0772ac629b4b050958514d2985521d9a38929b452213222759729028be8cf75
font_02_sfnt_off0000ed2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED2E 16756 bytes
SHA-256: 779ab49c6833f780bade332696c71cd72e8e656b53c33cb00497369322e7d0d6