Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b20f865aa2397c8…

MALICIOUS

PDF

71.1 KB Created: 2021-06-24 05:49:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 1fd48632fefa034b377c3f57c7f062e3 SHA-1: 473ab6dd2eb021049f5c05cab95d1b18d49e174e SHA-256: 2b20f865aa2397c8fbd3c4794b71c84e0b4bb93de8187491847d3df1b23101ae
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

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://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/31i1j8v1a9cr08b7m6259o35qc/niwuliwosamogosik.pdf In PDF document text
    • http://adance0112.com/upfile/editor/file/leduwabin.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160924b6eb0541---kowunuz.pdfIn PDF document text
    • http://nesthomes.in/userfiles/file/zavojumixasoronuvulij.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/pavexijumewitabiporeti.pdfIn PDF document text
    • http://gernano.eu/gfx/userfiles/files/zoguliboguvo.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210605_9F81B1658348EED4.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/881b4cc40b709c66e39f422e9d3018cf/85457849904.pdfIn PDF document text
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/4d27c3b78809930e2862277943841148/fisalev.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/sviautknk0b52jdvv5d2hblesa/76114332207.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ccc5d83463b---kotoxosoxamivodiwe.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/30b9e2351e96f237b337c246bb756a1e/rufivewadomupunap.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/sga8vmruu9n2rfvi5stskivr43/wepagep.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/ziganevexobutuk.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160775abe4b814---1337045037.pdfIn PDF document text
    • https://www.nosolodespedidas.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608378fc8c1a9---masupul.pdfIn 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/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=pdf+add+stampPDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dadb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDADB 5060 bytes
SHA-256: ea2ff390d511908c966949cdc2f1b88783adbd18e7f704ad04f37af041759e77
font_01_sfnt_off0000ec09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC09 10508 bytes
SHA-256: 5fd3c276a491074608c808305c8b64c0b8cbc33181f8007b7ba6a22c690194b1