Malicious PDF — malware analysis report

Static analysis result for SHA-256 512a546b0cd603c7…

MALICIOUS

PDF

74.2 KB Created: 2021-06-09 17:07:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: a33d3879f1893b144005e45a6ca8e827 SHA-1: fd434048c2725a8dc2ea5ebac90962243d270e85 SHA-256: 512a546b0cd603c7cdb795c6e7cbfa30c1b77c5c46180007620251e21750d041
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised websites and disposable hosting, likely intended to redirect users to malicious content. The PDF structure itself is also noted for containing duplicate objects, a common obfuscation technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=printable+12x12+multiplication+chart PDF link annotation
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/5bf971ecafc473b62e27eeea3b62521c/bowuzezabobojagu.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073a1f248198---82020291815.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/6183e53ab9a5177e0b883e6667db5aa2/jimujobofel.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608de3057e69d---58199766636.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/9d97a03dcbe6fe04f24dfd462362d23f/36842404895.pdfIn PDF document text
    • http://aimic.com/userfiles/file/muvemovezatolalopuze.pdfIn PDF document text
    • https://autotrans911.com/thread/admin/uploads/file/waranesi.pdfIn PDF document text
    • https://kede.org/userfiles/file/22975961863.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/rcpvbuj1n5edon2ruume098on0/22225905539.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071d40f34f39---46261571836.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095b5449e981---29559116940.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/3lpbkkga96pdk4bo3kimhu28ou/20747720247.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/xajalavureru.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a213172ca9a---peronuwadikedajinirafej.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd349f3c269---20990203503.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e58a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58A 5388 bytes
SHA-256: 5a8d4bd987c0f8a9b8c1cd41b9bf668ac20ab7688cfe7d586e6bc35e1cedf3bf
font_01_sfnt_off0000f7ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7BA 10672 bytes
SHA-256: 37054b511effaaab5e09a8f9d2ce92a40423b921383cfabaf12e784fbfbd4a3b