Malicious PDF — malware analysis report

Static analysis result for SHA-256 80aac9d16b0b0d23…

MALICIOUS

PDF

69.0 KB Created: 2021-09-24 18:34:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f90d8c255196f1dd65778d49979a9baf SHA-1: 762a068fc863f8da729634e048fcc48692452851 SHA-256: 80aac9d16b0b0d230c552539cea3c38f2c27bb313dc337c009e0c8e6c0656973
156 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 compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct textual clues to its purpose beyond what is inferred from the heuristics and URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://chcial.ru/uplcv?utm_term=what+is+the+backcourt+rule+in+basketball PDF link annotation
    • http://kiszelyugyvediiroda.hu/docs/file/xemodizegirawerofopa.pdfIn PDF document text
    • https://ises.smithpressautomation.com/phpsites/vertical_living/uploads/file/69631700580.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613eebdbb2db2---35234107247.pdfIn PDF document text
    • https://actsonics.com/uploads/files/202109111435286753.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/denawete.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/l65dm2s7d4lltv12789ag2ggeg/wofodiwep.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/82034641723.pdfIn PDF document text
    • http://thaimassagemodel.com/ckfinder/userfiles/files/39437993226.pdfIn PDF document text
    • http://wronba.com/uploads/wysiwyg/file/17017195857.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c462397f8d---61836728863.pdfIn PDF document text
    • http://fu-xin.tw/uploads/files/202109102238342672.pdfIn PDF document text
    • http://eltdb.com/UserFiles/files/19920872305.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/19772512806.pdfIn PDF document text
    • https://dichvuketoansg.com/luutru/files/39053721823.pdfIn PDF document text
    • http://abogadosaguilar.com/ckfinder/userfiles/files/dupuwovulofevikaxisulom.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/14733917685.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/850c68121796666447520db8dccf405c/69863596056.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/5923239890156390155f1fc140d9bcf6/pidigududibeko.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/lovofasu.pdfIn PDF document text
    • http://musorcentrum.hu/files/article/file/99795198559.pdfIn PDF document text
    • http://tabouligrill.com/ckfinder/userfiles/files/61059138352.pdfIn PDF document text
    • https://peintures-descours.fr/fichier/files/varisubalexegag.pdfIn PDF document text
    • http://kool-house.com/upload/editor/file/xunogiliwisasarixikugade.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_off0000b102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB102 10652 bytes
SHA-256: 97563a1b2caf9be0957a6a90852db96148cadafb7c5da0c3c728e02cf5b72ebf
font_01_sfnt_off0000c95e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC95E 14536 bytes
SHA-256: 604c03c5d41964eeb6066dfa204c834064cdf525703feeca7b71571ea4b5d913
font_02_sfnt_off0000edbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1