Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca4125c70db07769…

MALICIOUS

PDF

75.1 KB Created: 2021-02-15 07:59:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: f541e7852052480516d9d95f44da2165 SHA-1: 2c33422da908edd61bfc1d9fc14b929e7389d98e SHA-256: ca4125c70db07769bceffb9996750dcad6778bc425003e5bfe519558219a21a3
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, with one specifically pointing to a keyword-related search on 'jacksth.ru', suggesting a lure for users searching for specific manuals. The PDF structure and embedded links are indicative of a phishing or spam campaign, likely using a spearphishing attachment vector. No scripts were extracted, but the PDF's nature strongly suggests it's designed to redirect users to malicious sites.

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://jacksth.ru/wix?keyword=hobart+am14+dishwasher+parts+manual PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4414514/normal_5ffa6c1185519.pdfIn PDF document text
    • http://zhigina.ru/canon_eos_rebel_t5_manualaaiqc.pdfIn PDF document text
    • https://cdn.sqhk.co/fodexuxefeba/hqgdSjd/lupasaragezofilaf.pdfIn PDF document text
    • https://cdn.sqhk.co/gadewekunel/jj4lghl/82516099394.pdfIn PDF document text
    • https://cdn.sqhk.co/wezupobuwab/i0idhhr/nexategujozuloxuzi.pdfIn PDF document text
    • https://belinadojo.weebly.com/uploads/1/3/1/6/131607131/2f21129eea50.pdfIn PDF document text
    • http://livethailand.fun/masha_and_the_bear_coloring_online_gamesvld6q.pdfIn PDF document text
    • http://academic-club.ru/aiims_assertion_reason_bookx5cyk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388827/normal_5fea1cc5e6a0e.pdfIn PDF document text
    • http://fasibada.22web.org/begodegapegutojunizo.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/fadadedezeker/bernina_serger_334ds_manual.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_off0000ea16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA16 5532 bytes
SHA-256: be982a9c644ff0f50688f1857962f2caa54034b440d29d8dbe261ac3a744ede2
font_01_sfnt_off0000fcce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCCE 10192 bytes
SHA-256: 5f0301475437074872f084651da65298e3da549d7452e1f556a7d2fd4e102bfe

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