Malicious PDF — malware analysis report

Static analysis result for SHA-256 24768a7b66976048…

MALICIOUS

PDF

88.2 KB Created: 2021-09-08 14:01:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bd3b5252c3a8330446d2860e6b25cdd1 SHA-1: a96a51adb800e28adca9d3d714ba4f2708a6abd7 SHA-256: 24768a7b66976048a4786e7f468a8928cafee5ca323d379a7f8cb649640b0af9
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with multiple URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest the document's purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613828994d35d---nizoduromu.pdf In PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/oj9khuc7t2bk48m1cgvcdf528f/45607752286.pdfIn PDF document text
    • http://kronikarp.pl/ckfinder/userfiles/files/kepabowisodesifaraf.pdfIn PDF document text
    • https://terlickodds.cz/www/www/fckphotos/file/xopos.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/xukiroxoxetobabid.pdfIn PDF document text
    • http://superfasttv.com/uploads/files/bagiwebowawixa.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130e13d2e6d8---34330864715.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16133ed0fe0645---40995630513.pdfIn PDF document text
    • http://sushistoryus.com/uploads/files/91578792697.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/95421780786.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/89322402200.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/dagitofatiwuto.pdfIn PDF document text
    • https://beamstraffic.com/amb/userfiles/file/nogazapesevitusijepig.pdfIn PDF document text
    • http://radecznica.pl/userfiles/file/molarerowibebalufewalekif.pdfIn PDF document text
    • https://ecotranslation.ca/upload/editor/file/diliga.pdfIn PDF document text
    • http://jjc-dev.com/userfiles/file/9857806385.pdfIn PDF document text
    • http://mariopresto.pl/userfiles/file/towikoziti.pdfIn PDF document text
    • https://pr-dienst.ch/file/71781144844.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/a335d83e7b89678dc40a52f1c4369f7a/kamuxokinu.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16131f2b126c36---zazodujitufuwokofovop.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612ece0353120---27607546267.pdfIn PDF document text
    • http://ingfrimale.com/userfiles/files/rametabirewisuj.pdfIn PDF document text
    • http://www.mab-solutions.fr/upload/file/kesokinuwisutavafu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=human+reliability+analysis+pdfPDF 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_off0000ef1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF1D 10884 bytes
SHA-256: 939df8ac5c2e0034f4900977f1f9fe9f0415fe1717b83d924b59bae6f3659070
font_01_sfnt_off00010800.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10800 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012012.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12012 19740 bytes
SHA-256: 7134128c616468f2f4c1dae19435590321e772c5112b7758b8cabb6b37f592dd