Malicious PDF — malware analysis report

Static analysis result for SHA-256 b61885e19147af8e…

MALICIOUS

PDF

90.0 KB Created: 2021-06-18 20:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: b270175eebd3616c7de6d02c2ff4cf3e SHA-1: 49fcca9ae080922e188d3b73d4e74fe284080f44 SHA-256: b61885e19147af8e9f333f2bbc8011f233bb5da4b8e32c2c75e84a082d72ce1f
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://technok.cz/wp-content/plugins/super-forms/uploads/php/files/22aba888e58ae4dd33986719244f5745/55759549454.pdf In PDF document text
    • https://gachbinhduong.com/upload/file/20222169791.pdfIn PDF document text
    • https://alutat.com/data/file/87781620333.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff5453126a---vusidiganigajunarekonor.pdfIn PDF document text
    • http://cloverpark1959.com/clients/51168/File/fajuno.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/a2ec22dae5608cdb1526353e0c44fb7f/limaneni.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/xavidosubupuveme.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160aa78f9483de---52611216738.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093de7f4610d---79271777498.pdfIn PDF document text
    • https://namratalakhotia.com/userfiles/files/miribugowim.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/74493086f7329faeeb945111a8b502aa/98081539035.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609f4b40f23ad---25629554891.pdfIn PDF document text
    • http://asokmontridental.com/userfiles/file/11838810737.pdfIn PDF document text
    • https://anfauglir.com/images/file/timimubugejoroz.pdfIn PDF document text
    • https://iominneapolis.com/wp-content/plugins/super-forms/uploads/php/files/ce1f8e31ab7b5f39751ba60307fa8b0c/fikemeguga.pdfIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=bamini+keyboard+layout+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000fdc9.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xFDC9 22912 bytes
SHA-256: 351ec5308d9d12530da06527801b7e594079920fc62faefec02c12acbf61f862
font_00_sfnt_off0000eb98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB98 5364 bytes
SHA-256: aa3fe13118671963d036af9ed868ac9904a9fbfe520addd513111fec47e6bf88
font_02_sfnt_off00013228.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13228 12568 bytes
SHA-256: 1fa399f0721d3315b7cd0545e03d6be5dfd669378eae87d532839655167d3045