Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dfc8c9a77bdd981…

MALICIOUS

PDF

77.7 KB Created: 2021-03-17 23:02:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f35e20986ea608a37e9d0f04e6c7b80f SHA-1: b1eccab071b0b5b2ebaf97ed120a4bdeb7a36bd1 SHA-256: 4dfc8c9a77bdd981bfb24a2ad87a1a00515b742d3000102ed5e4a2976bbd932d
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute further malicious content or phish users. The document body, though heavily obfuscated, contains text related to a worksheet, which serves as a lure to encourage users to click the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://ponafet.ru/123?utm_term=direct+and+indirect+object+pronouns+worksheet+answers
    • http://dipunag.getenjoyment.net/pdf_evangelismo_con_fuego.pdf
    • https://figunetu.weebly.com/uploads/1/3/4/3/134353482/1603280.pdf
    • https://guxitokos.weebly.com/uploads/1/3/2/6/132681611/961819c.pdf
    • http://sekujirimabasas.getenjoyment.net/programa_de_honores_a_la_bandera_del_20_de_noviembre.pdf
    • http://davorivugexawu.sportsontheweb.net/rebolarilureribalabuxi.pdf
    • https://befufagu.weebly.com/uploads/1/3/1/3/131384284/7656919.pdf
    • http://vekogevev.22web.org/how_to_use_black_and_decker_steam_iron.pdf
    • http://kugimanuvo.iblogger.org/zotudevatumujem.pdf
    • http://jorowijedo.mywebcommunity.org/ferofixowijatifavirajibo.pdf
    • https://jazebaza.weebly.com/uploads/1/3/4/6/134662006/3530115.pdf
    • https://sijerixo.weebly.com/uploads/1/3/4/0/134042725/7152440.pdf
    • https://pekumovulimezel.weebly.com/uploads/1/3/4/3/134363026/pepoxekeleva-fenatuloxat.pdf
    • http://bibopasaxuvibu.mypressonline.com/how_to_pronounce_zao_in_chinese.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/takateg/68016346609.pdf
    • https://s3.amazonaws.com/sezewu/manager_not_working_android_pie.pdf
    • https://s3.amazonaws.com/domegagowevag/58975387652.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ecc7.bin
a23914337fb34a4e5ea2079d1c29a92e768a8e79a25a14a96f216f4a222c2e03		 pdf-font-stream PDF embedded font (sfnt) at offset 0xECC7 5500 bytes
font_01_sfnt_off0000ff8c.bin
94396856d88f130ddef870ba8098199e50f4615f4b23fb0a7fa12848bf072a17		 pdf-font-stream PDF embedded font (sfnt) at offset 0xFF8C 12172 bytes

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