Malicious PDF — malware analysis report

Static analysis result for SHA-256 aef6c70529198d57…

MALICIOUS

PDF

164.0 KB Created: 2021-02-22 16:50:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: de86eb8c787889f8432d8b015ec488b9 SHA-1: d9522d225608fcc92d2f1bab01d1646d62113b43 SHA-256: aef6c70529198d5755d7b0cd2629fd0899caf89856b86a774ac0bfb6dad4df8d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9315

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://maypoin.ru/123?utm_term=underdark+knight+3.5 PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4529780/normal_5ff54910ce316.pdfIn PDF document text
    • https://biwizodem.weebly.com/uploads/1/3/4/6/134650183/893f9e966.pdfIn PDF document text
    • https://sovevalejuwup.weebly.com/uploads/1/3/1/8/131858043/5d568dc32.pdfIn PDF document text
    • https://mutakisutuw.weebly.com/uploads/1/3/4/7/134768563/nuxuk.pdfIn PDF document text
    • http://vasazuruxu.iblogger.org/logical_abstract_reasoning_test_with_answers.pdfIn PDF document text
    • http://pressit.space/dolls_house_ibsen_download97kwj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/mulerux/99482412877.pdfIn PDF document text
    • http://faguvepeme.rf.gd/catlogo_mary_kay_2018.pdfIn 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_off00024b80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x24B80 5252 bytes
SHA-256: 2625056ab3f5e9e00921e4dc7fc0f611de37884e9ede5069d50076ef32b21f37
font_01_sfnt_off00025d66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25D66 11416 bytes
SHA-256: 6dc325829582b59162620d5d92685d734151083d6d6f16ac0f9b8a695ff84025