Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a2fd4a448aa3bb9…

MALICIOUS

PDF

86.1 KB Created: 2021-09-22 12:48:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d3e9e4d0d8a6ef67b19c47f30aa72891 SHA-1: 0ed1110f5e3bbf162c47d151d3d50a22522ea707 SHA-256: 0a2fd4a448aa3bb934645626485d9c2737ee0fc6a8265b3bee0dcc0f4916d509
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS upload directories. These links likely serve as lures for phishing attacks or to distribute further malware. The presence of multiple compromised hosts and disposable hosting suggests an attempt to evade detection and maintain operational resilience.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/ikn1mfsbfi351obn5166alofv8/ginumomalop.pdf
    • http://residencelesaline.it/userfiles/files/81156592454.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/b7b3ee44825210b12401e344301ca0b8/rifuvekudiligonetixuvo.pdf
    • http://simp-q.ru/userfiles/file/fevikofelivalixerovi.pdf
    • http://klimagra.pl/images/wysiwyg_img/file/7308225200.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161342aed83bcb---dovuturizolugonu.pdf
    • http://transbur.ru/admin/ckfinder/userfiles/files/46802521697.pdf
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/30482554731.pdf
    • http://vucert.vn/uploads/files/59640300717.pdf
    • https://2ruoteexpo.it/ckfinder/userfiles/files/xiput.pdf
    • https://xn----7sbbg1ddpkdc.xn--j1amh/uploads/files/73162279233.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161416a2957170---81274748550.pdf
    • https://doktor-ara.com/userfiles/files/donumuviguletikat.pdf
    • http://creativecoms.net/userfiles/file/nibajebudubeturidajudovaf.pdf
    • https://greenways.at/userfiles/file/67183665616.pdf
    • https://ateliersmq.com/pevron/www/img/file/wanagiravidexogamodefa.pdf
    • https://ln80.cn/filespath/files/20210905085753.pdf
    • http://ephtour.com/FileData/ckfinder/files/20210921_4C9E3B998643363F.pdf
    • https://maturana.cl/upload/file/faliwo.pdf
    • http://easy-sleep24.de/shop/images/editorfiles/file/vanupuruxararu.pdf
    • http://ktcyy.com/ckfinder/userfiles/files/losegesezozubijajebabal.pdf
    • http://stillincontact.com/images/mails/file/guvaludewe.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd8ec5c60b---90530650507.pdf
    • http://inter-travel.hu/_user/file/zupegaketuruzorofemus.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=asphalt+9+offline+mod
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb6f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB6F 16792 bytes
font_01_sfnt_off00010381.bin
30951e9300625810d9baa9335250e589cf2df83c605a5d6f607167b1e7d6219c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10381 18004 bytes
font_02_sfnt_off00013227.bin
0e546f9c275e0bf23fe4eb7445dedb83d20b6eb75aa6888cdb2684d9779a8bf7
pdf-font-stream PDF embedded font (sfnt) at offset 0x13227 10812 bytes