Malicious PDF — malware analysis report

Static analysis result for SHA-256 b67f91a20bbfb925…

MALICIOUS

PDF

67.7 KB Created: 2021-02-25 11:00:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 74a20e347dc0162e81140c44064e2556 SHA-1: a263acc22b30ce8b261ac04a4c774c22040e1d61 SHA-256: b67f91a20bbfb925a009063ab2f5bf2a895079f54b046eda6d4d29bd5e259256
126 Risk Score

Malware Insights

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

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains numerous external URLs, many hosted on disposable domains, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using small PDFs for link farming on disposable hosting, often associated with phishing or malware distribution. No scripts were extracted, but the presence of embedded URLs points to an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://jottigo.ru/aws?utm_term=ejercicios+de+quimica+organica+alcanos+alquenos+y+alquinos+resueltos PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4368474/normal_5ff4c9ca41fcb.pdfIn PDF document text
    • https://cdn.sqhk.co/guzoladip/vhegc8p/7521955722.pdfIn PDF document text
    • http://espacecmb.xyz/vuwupavorememidusobasowol5q21l.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414357/normal_6011293369536.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369189/normal_5ff22ef604b2c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4404488/normal_5fc98616e5e78.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386095/normal_60192a916cf59.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490125/normal_60222b46874e7.pdfIn PDF document text
    • http://edarudost.online/jidinidwzwag.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413696/normal_60095f5ee7793.pdfIn PDF document text
    • http://remont-kvartir-otzyvy.moscow/29343485002udyje.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376374/normal_6021d586ccc0e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4428045/normal_5fe83c64890f0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486351/normal_6019542ddf54c.pdfIn PDF document text
    • http://zatoboyvibor.fun/tulozaxurirejabejuruvanupcs3op.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/bopuxosavubare/paxitanodogojifejiga.pdfIn PDF document text
    • https://s3.amazonaws.com/rezugekolaba/sword_art_online_android_games_list.pdfIn PDF document text
    • https://s3.amazonaws.com/sisaxu/delowerunonizididijures.pdfIn PDF document text
    • https://s3.amazonaws.com/widofafane/xadelol.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_off0000cc4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC4B 5520 bytes
SHA-256: ad0efe9025bb82a7be0e5eeb69cdcd47989f63957ae53f2aba5211c570851a57
font_01_sfnt_off0000defd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEFD 10320 bytes
SHA-256: 8bcf58efca756ae0a223373395a8709d32d529158006c156846314d5857a5e4f

Open this report in the interactive analyzer, or submit your own file for analysis.