Malicious PDF — malware analysis report

Static analysis result for SHA-256 86cf333e57e4e737…

MALICIOUS

PDF

35.9 KB Created: 2020-11-03 16:11:07 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 29509628968fa6f02db0a679fbbb7a7e SHA-1: db253defad9cab5a62463e22e0164ca3f653217f SHA-256: 86cf333e57e4e737825d1164d4b1e90abfd2d5996bd6cfb002ea142774e58d05
124 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, one of which, https://cctraff.ru/strik?keyword=everfi+future+goals+answers+math, is flagged as a malicious redirector. The document body and embedded links suggest a lure to educational content to disguise the malicious redirection. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://cctraff.ru/strik?keyword=everfi+future+goals+answers+math In PDF document text
    • https://kuzaloxamuw.weebly.com/uploads/1/3/1/4/131406684/954920f9.pdfIn PDF document text
    • https://kivepuwepadile.weebly.com/uploads/1/3/4/3/134392404/0526ccdb6f6a.pdfIn PDF document text
    • https://xodunutejoxefis.weebly.com/uploads/1/3/4/4/134476009/fitoxurewaw.pdfIn PDF document text
    • https://jawowigo.weebly.com/uploads/1/3/0/7/130774982/55a7c75aa.pdfIn PDF document text
    • https://vogemafebin.weebly.com/uploads/1/3/4/2/134235603/jesesefuru-jojorakipuxufa-nofojexeb.pdfIn PDF document text
    • https://ranerenonosojib.weebly.com/uploads/1/3/1/4/131483420/pozakexobufiv.pdfIn PDF document text
    • https://tarirubawapub.weebly.com/uploads/1/3/1/6/131606173/a5e1ec36.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/texifaxepag/wiloritijejaxosakela.pdfIn PDF document text
    • https://s3.amazonaws.com/tudawufed/ligalemopozegik.pdfIn PDF document text
    • https://s3.amazonaws.com/jesidofefe/ramuxadolubelutasaxojilo.pdfIn PDF document text
    • https://s3.amazonaws.com/jidosatikim/sociology_of_education_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_off00004d32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4D32 5292 bytes
SHA-256: 29ee6b739790e9de6f6317b28661254bab64d55f35801b014e8060641376632f
font_01_sfnt_off00005f24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5F24 10608 bytes
SHA-256: 41c2cb02d85ebf2f74d1048391211a373831881ba1d9e1d6c58ec04c27a2b742