Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcf7ba4450514fae…

MALICIOUS

PDF

71.8 KB Created: 2021-06-24 20:21:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: c120b57ad6f7d13871aedd59970f24a6 SHA-1: 5fe01352b8dfadc10901bdbf04564b971e8bf679 SHA-256: dcf7ba4450514fae083f960bc84abde17eb5cc3c18893fd84e2f937f7f971b1c
176 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The presence of PRC/3D content and duplicate object bodies are common PDF obfuscation techniques used to evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • PRC/3D content in PDF medium CVE related PDF_PRC_3D
    PDF contains PRC 3D content. PRC/U3D parsers have been a recurring Adobe Reader attack surface; treat as a related parser-exploit indicator rather than a specific CVE match.
  • 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://allytemp.ru/uplcv?utm_term=testbild+drucker+pdf PDF link annotation
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/9f9e03669c8e645b358a834f5ac9daa4/tepesosidid.pdfIn PDF document text
    • http://skncn.com/u/files/demeduxameso.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/1334887261.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/v9tbs1qff39kdhosb5vk699id3/korokoxosajovix.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2d6a255ba---32664309046.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/0p4ud87sqnlqlsph468r279n9p/21938099775.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cac9b908f39---99659239331.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/fozegiwazenosukerorowizo.pdfIn PDF document text
    • http://ztkammer.at/uploads/file/rirafifurezozisukeba.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1609555e436c0a---80594823954.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16084d44a841f0---19843108411.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/2e8bd6fd0c5a86d1f1003d1186d565c1/vamavasakaw.pdfIn PDF document text
    • http://crystalsteakandstogie.com/clients/1/1d/1dbb6d5698303b6304ae84622e226a19/File/98491230646.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/921548a04260b720db3fdd9b243e9ff0/7039342343.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/3nkkhhurnrb743jc22mtgo0gs4/58630560038.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_off0000dbe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE5 5092 bytes
SHA-256: a63c706d3c27697578437b4d3a19a603eff30b7bc15fab4d4eff921414cf6ee2
font_01_sfnt_off0000ed41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED41 11400 bytes
SHA-256: b8d4920c997ca3ea9afe38009d5ac47074d37344d1b44e3b02b9ca8de61b2a07