Malicious PDF — malware analysis report

Static analysis result for SHA-256 59ef10077948e1c6…

MALICIOUS

PDF

71.8 KB Created: 2021-05-24 21:29:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 9bb6d3c0c70d8829e58ba0b396834d5a SHA-1: 2e820c84cdc60355589ae3421b9aa937f90a23c5 SHA-256: 59ef10077948e1c6e88417f4314a4d879867a5a5c556632aaa25b3c4fd86c937
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links pointing to compromised CMS upload directories, suggesting it functions as a link farm. The embedded content, though heavily obfuscated, likely serves to obscure the malicious nature of these links and potentially exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085b5dc9f5ac---35608200634.pdf In PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609da63e9424a---tezuj.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/velutinenetakutu.pdfIn PDF document text
    • https://blueridgelightingandcontrols.com/wp-content/plugins/super-forms/uploads/php/files/8644d8c58d13c0920a89f566cb7c90af/96330654889.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6dfcf1ca5---79566724912.pdfIn PDF document text
    • http://brette-animation.com/userfiles/file/39207198948.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/04ce2fb828f73ca3aaecdec4654bb3b1/javafajotafixepaxuvinu.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/735aad11f181d4b7d8360a6ebb8f8de1/lenoleteluvon.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608011fa243b4---87740671099.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/5920461966.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/48j1an9qlm17obbigid673ndh7/90531649612.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/2073ee63b914d4d9f2a7044a8a302802/32879631944.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607085a35d89a---8802305115.pdfIn PDF document text
    • https://pablohernandes.com/wp-content/plugins/super-forms/uploads/php/files/236daeace5e5a71840cad0b88ea0cf5f/12095318168.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/f6h6jm26vv2s6u5klrds83pd44/24198477402.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/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=how+to+sing+better+in+smulePDF 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_off0000dac9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC9 4988 bytes
SHA-256: 8509d2e67561a0ab66ad84ed0762ac8a061bb8854f06c07eed19333934477bf2
font_01_sfnt_off0000ebbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBBC 11232 bytes
SHA-256: b66d3b47b640e6e2c9c44408e639505cab34ba250b6ce2a2b2c6e4587c1b3552