Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1e0389a63343f4e…

MALICIOUS

PDF

93.2 KB Created: 2021-09-19 14:11:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 8fb071a22708fac42e52d964287fdd32 SHA-1: 846e969530694be92c8c88cf1653535cd0192d95 SHA-256: f1e0389a63343f4eea69f359b609a316675b554d8a8a6fe3c39a1a8c0b3de7e1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or are structured as link farms, indicating a likely attempt to redirect users to malicious sites. The `wkhtmltopdf` authoring application suggests it may have been generated programmatically for this purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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://chcial.ru/uplcv?utm_term=arduino+bluetooth+controller+app+source+code PDF link annotation
    • https://nepalonlineexam.tisaracademy.com/userfiles/files/powomenelajefesegepazexaf.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16140f459ea575---jirewekexijigizikomunuw.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/55095115615.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/samalomijokojajof.pdfIn PDF document text
    • https://vresponse.net/userfiles/file/jexopetel.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/xuzagaditopurutubo.pdfIn PDF document text
    • http://architettipassarinmarzotto.com/userfiles/files/ziwokeva.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/40367634231.pdfIn PDF document text
    • http://revize-elektro.info/UserFiles/File/xovukaj.pdfIn PDF document text
    • http://coreaad.com/DreamDataUpload/file/70053585941.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131022ccedfe---wokadikafubi.pdfIn PDF document text
    • https://littleedupark.com/ckfinder/userfiles/files/48608655988.pdfIn PDF document text
    • http://caycanh.vn/images/fck/file/fosesupinudu.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/66265728594.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161386710b1182---91830656177.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/futaxotagekurora.pdfIn PDF document text
    • http://tyextractor.com/d/files/balobajirebisazowefokad.pdfIn PDF document text
    • https://gsm.company/ckfinder/userfiles/files/41541183423.pdfIn PDF document text
    • https://media-get.ru/userfiles/files/36244719370.pdfIn PDF document text
    • http://quiltingacademy.com/fckeditor/userfiles/file/30015574722.pdfIn PDF document text
    • https://muacash.com/webroot/img/files/68240700421.pdfIn PDF document text
    • http://105chers.netsociality.com/upload/files/wifefunuwekegukinezupot.pdfIn PDF document text
    • http://sumisaedu.com/FileData/ckfinder/files/20210909_951E22FCB5ABB6C1.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://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_off000105cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105CB 18432 bytes
SHA-256: af1dbd9e4a9738e44fad6a2cff9af8b5c06810fc686c14753572f5883c01c27a
font_01_sfnt_off00013645.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13645 10832 bytes
SHA-256: 8e78ff747a0cc5b6825100725a35fb770083a12c370ceded8c445300050d53a2
font_02_sfnt_off00014ef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1