Malicious PDF — malware analysis report

Static analysis result for SHA-256 78b618f3519e8c1e…

MALICIOUS

PDF

99.9 KB Created: 2021-04-30 13:31:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 83aa655eb57c69bf815bfe9bebed6cde SHA-1: 05a6fc5a89a3365962feceee035e972f5805daed SHA-256: 78b618f3519e8c1e493e76ce2bb2075c2f0affe05ded299b0526d7b99aff8a3e
126 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic firings, particularly 'PDF_SEO_DISPOSABLE_LINK_FARM', suggest the document is designed to host a large number of links pointing to potentially malicious or phishing sites. The embedded URLs and the structure of the PDF support this, indicating an attempt to redirect users to external resources for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://druttle.ru/strik?utm_term=scholastic+1st+grade+jumbo+workbook PDF link annotation
    • http://tarekupi.scienceontheweb.net/batgirl_mask_template.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404969/normal_5fe6a02fdd0f2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473619/normal_606157de489e2.pdfIn PDF document text
    • http://fipoziwebetaz.22web.org/bujozuvuxepojamijuse.pdfIn PDF document text
    • http://magexaxajatadog.getenjoyment.net/customary_units_of_measurement_chart.pdfIn PDF document text
    • https://vobubivozabu.weebly.com/uploads/1/3/4/3/134320693/fukaloxukuto.pdfIn PDF document text
    • https://rofasotukez.weebly.com/uploads/1/3/0/7/130740205/3cf63a8eb1716.pdfIn PDF document text
    • http://mutomew.22web.org/8026236502.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4388280/normal_5fdf971f31c8f.pdfIn PDF document text
    • https://pibiwija.weebly.com/uploads/1/3/4/8/134896476/98ed30f5cc3c979.pdfIn PDF document text
    • https://liroxinumapidaz.weebly.com/uploads/1/3/5/3/135348088/nejevaxunor.pdfIn PDF document text
    • https://tubivafidet.weebly.com/uploads/1/3/4/8/134886435/c6da1.pdfIn PDF document text
    • https://nugaruxiboxora.weebly.com/uploads/1/3/0/7/130738781/8338139.pdfIn PDF document text
    • http://bizifemodefi.mygamesonline.org/tamil_language_learning.pdfIn PDF document text
    • https://rivabugejovo.weebly.com/uploads/1/3/0/7/130739095/3f5f4fc48985f2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/648c9723-b71d-4706-9a70-c4b8d9c2a7d3/67408348103.pdfIn PDF document text
    • http://gijufebevavudep.rf.gd/11704458912.pdfIn PDF document text
    • http://topemuzopapegu.epizy.com/28483049154.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cc06d2c0-b70b-4245-8f1b-2f7f508f088f/44525129674.pdfIn PDF document text
    • http://lopafulobitap.atwebpages.com/7410368658.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2a1847d1-0628-4292-a5c4-f7a76875be54/charger_escape_walkthrough_text.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e6db25e-0b9c-44ea-883c-d71e13f20010/42367746143.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012b81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B81 5880 bytes
SHA-256: d6da141c9429c1ed9bcf5bf6e43719b0e6d51019dffcf61a50b3bc53775eabd1
font_01_sfnt_off00013f70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F70 14364 bytes
SHA-256: 1b428018f94e1570dff9041289d572eec35d043b7c0175b266f1bded3c441329
font_02_sfnt_off00016d30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D30 16092 bytes
SHA-256: c9557d91917e40dbb2ce09b7ef560a04a9a832ffe2ebcac6b50408a58351272e