Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae84f2ddad5944e0…

MALICIOUS

PDF

89.4 KB Created: 2021-10-06 12:08:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 433efc67c5e0434ee581627d0aa87a54 SHA-1: e3c7691010e2e5c6dbfbb6f49b9e4f5ad73ad266 SHA-256: ae84f2ddad5944e08968271caa36c63cb399ec907d19688e89368acbf2b341d8
126 Risk Score

Malware Insights

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

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 embedded URLs pointing to potentially malicious or disposable domains. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://wittymall.com/multimedia/userfiles/file/17530998264.pdf In PDF document text
    • https://prokoncept.hu/admin/blogfck/image/file/22124393794.pdfIn PDF document text
    • https://inprovitbolivia.com/ckfinder/userfiles/files/17496861198.pdfIn PDF document text
    • http://kirakuramen.com/uploads/files/35902865971.pdfIn PDF document text
    • http://spartapr.com/images/upload/file/suwesopixotofipizuw.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/walimomujiguku.pdfIn PDF document text
    • http://fleshlight-tw.com/userfiles/file/39395301911.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/ronixonepugiwi.pdfIn PDF document text
    • https://teater77.nl/userfiles/file/pigubimufetamifak.pdfIn PDF document text
    • http://poorclarescork.ie/images/buwozini.pdfIn PDF document text
    • http://llux.vn/uploads/files/pozufularifudifegijexib.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021090308235416.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/demonofufawazifag.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/pomilasuzi.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135e5f5c6aef---julovuxatolu.pdfIn PDF document text
    • http://cl-pub.com/files/files/45936966047.pdfIn PDF document text
    • https://weishinclinic.com/uploads/files/202109210947342182.pdfIn PDF document text
    • http://l-max.ru/userfiles/file/jomemedajekemusur.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/rabasojanalanu.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/75904901138.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/guxekerumumerini.pdfIn PDF document text
    • http://accapierre.it/userfiles/files/39931754379.pdfIn PDF document text
    • http://celyroknaterase.sk/editor_uploads/system/files/wenikilirisabagobazo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=paladin+of+the+end+novelPDF 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_off0000f21f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF21F 21076 bytes
SHA-256: d7fdb75f0bdf7ea7bca23b8a4dfdda3f89bfb75fbf6bfea04983a50a4c2e7af6
font_01_sfnt_off000127c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013fe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FE0 10252 bytes
SHA-256: 3d17074ec9642f86c58a39fdb2d56b08cec820118b83a147ba7f3e2853f38720