Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc73e93892796d40…

MALICIOUS

PDF

73.0 KB Created: 2021-09-23 18:49:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 542b2a92dccf1f72c31e364fb9ee77b0 SHA-1: 2ebe7fb090854ddcc397c5f69eb3f34af742e029 SHA-256: dc73e93892796d40c351a040a45ccb154836509406d26517fde99c976f1e9215
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous links pointing to disposable domains, suggesting an attempt to obscure malicious destinations. While no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest it's designed to redirect users to potentially harmful sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613016fded905---zuxoneludugesomibejiwatap.pdf In PDF document text
    • http://vitalenzyme.com/uploads/fckupload/file/52751428129.pdfIn PDF document text
    • http://kingsfci.com/userfiles/file/30352692747.pdfIn PDF document text
    • https://foundationkuzmanov.com/files/palazudogusiza.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148167861df3---25468608900.pdfIn PDF document text
    • http://ledspectrumthai.com/ckfinder/userfiles/files/56723925347.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/9728577215.pdfIn PDF document text
    • http://nawarashop.com/phya/ckfinder/userfiles/files/vopodugit.pdfIn PDF document text
    • https://pharma-tools.pl/galeria/file/zixomobariworugenuwu.pdfIn PDF document text
    • http://laiksmodalux.lt/app/webroot/uploads/userfiles/files/milovupudaxure.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/weloweruwijefizuwu.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/96167436910.pdfIn PDF document text
    • https://northwestconvention.cz/data/files/dudisagezemokadogudada.pdfIn PDF document text
    • https://tahitotfaluovodak.hu/ckfinder/userfiles/files/tanuvapurixusabexixa.pdfIn PDF document text
    • http://pro-elec.ru/ckfinder/userfiles/files/zedederujoreku.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/48503325060.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/9119078830.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/13417681075.pdfIn PDF document text
    • https://www.greenlakecruises.com/ckfinder/userfiles/files/dijoxini.pdfIn PDF document text
    • https://ceylanotel.com/firma/files/30145278737.pdfIn PDF document text
    • http://mskabel.cz/UserFiles/File/telofawagimuneviwuzaji.pdfIn PDF document text
    • http://reklama-v-sochi.com/ckfinder/userfiles/files/83166499031.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=impressive+ringtone+pubgPDF 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_off0000bc39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d44b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD44B 16356 bytes
SHA-256: d439d5afcf1427cd31c35a13570c59702aee20abb3796a6803ba0610cd13e9a8
font_02_sfnt_off0000fe4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE4F 10644 bytes
SHA-256: 1496d93ac54a480f662a0dc079217adccbbd4969a0781766e10afe1fa57a45c7