Malicious PDF — malware analysis report

Static analysis result for SHA-256 734911e2d7572529…

MALICIOUS

PDF

84.3 KB Created: 2021-09-20 12:47:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a7524a3886adf0b32dcc99474b2ad780 SHA-1: 350c77c74a6ff30b36a72429f019ab447f5d6545 SHA-256: 734911e2d7572529eff3efbb25094a56ee823ba2a04fc2f6201af75b1588511f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier as malicious. It contains numerous embedded URLs pointing to external PDF files, indicating a link farm or redirection mechanism. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM suggests these links are intended to obscure the true destination, a common tactic in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://chongqinghaohong.com/upload/files/15581877836.pdf In PDF document text
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/jabosuwogi.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/puwufamemabepezul.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/29552857760.pdfIn PDF document text
    • https://dascalita.ro/app/webroot/files/userfiles/files/3563764611.pdfIn PDF document text
    • http://laduses.nl/image/file/weximibugemerudepixute.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/76416998575.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146dec073ad4---63154526803.pdfIn PDF document text
    • https://lochoanggia.com/upload/files/nejenedagujitudedofuz.pdfIn PDF document text
    • http://normel.org/files/upload/file/komumasidabozijexixofe.pdfIn PDF document text
    • http://skontrolsengineering.com/file_media/file_image/file/levedidesi.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/bawusitafegodobebiwatofe.pdfIn PDF document text
    • http://www.gc-antey.ru/ckfinder/userfiles/files/tifigidobekunofon.pdfIn PDF document text
    • http://cjmfgx.morefriendship.com/upload/files/gezemu.pdfIn PDF document text
    • https://eetravel.net/file/13966312964.pdfIn PDF document text
    • https://hotelharmika.com/assets/userfiles/files/71540629289.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/bewapajurewosozuzoxiw.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/cba9b196715eb37323676b529c204c6c/17327010882.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/walabekibuxifevakenap.pdfIn PDF document text
    • https://intersensor.ro/v2011/Files/fck_upload/file/geguwelolawibumidajuput.pdfIn PDF document text
    • http://wronba.com/uploads/wysiwyg/file/fosupezaxenoxuwevi.pdfIn PDF document text
    • http://bk-plus.at/userfiles/files/vepatefenen.pdfIn PDF document text
    • http://insightonafrica.in/userfiles/file/35642690868.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/64315356803.pdfIn PDF document text
    • http://www.uds-myanmar.com/image/upload/File/72768678484.pdfIn PDF document text
    • https://maintogelonline.info/contents/files/83044126.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=android+reveal+effectPDF 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_off0000e512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE512 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD24 17972 bytes
SHA-256: d5c0ca2013e7704a34b332b8908a43c0049cb748118f663ba5418457c2a948d5
font_02_sfnt_off00012be1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BE1 10348 bytes
SHA-256: 1425aad06a566e0d303f65ed82329044e94b262ce2e808e995f1c6358a3af4ec