Malicious PDF — malware analysis report

Static analysis result for SHA-256 36dcf73d07f7e766…

MALICIOUS

PDF

88.1 KB Created: 2021-09-18 15:33:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 10405d94e853ec1e371aa2eb5a4e8eab SHA-1: 326034dcc5c24cdce492efc1f60d218d43fefcfa SHA-256: 36dcf73d07f7e76641fb01979622d6171b9feebfab6cef8df4bc7bcfc43f40b3
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. The PDF contains numerous embedded URLs, many of which point to potentially malicious content, suggesting a lure to download a secondary payload. The presence of a 'download button' heuristic further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://tccsrl.org/userfiles/files/koniviriro.pdf In PDF document text
    • https://plentis.eu/ckfinder/userfiles/files/bifedugiwawof.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/pepusu.pdfIn PDF document text
    • http://jd6618.com/jd6618/file/2021-9/file/LwpCms2021_09_03_13_47_03_6097.pdfIn PDF document text
    • http://321eastern-thailand.com/userfiles/files/gelasezeg.pdfIn PDF document text
    • http://alphanaturehk.com/userfiles/file/16089662799.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/xupozuregabopi.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/7de2bf1ba2390e3a44e01653d984bd8c/57337549625.pdfIn PDF document text
    • https://mgs-on-track.com/uploads/misc/files/25477479043.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/metuvodoxemosifirazo.pdfIn PDF document text
    • http://tcsm62.org/uploads/news/file/45520127871.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143d4811840c---98673909105.pdfIn PDF document text
    • http://agisinfo.ru/uploads/content/files/niwavibofonumasuvezoduxuj.pdfIn PDF document text
    • https://bonaparte.cappencms.com/templates/files/xoxesomukog.pdfIn PDF document text
    • https://prevodi-plovdiv.com/userfiles/file/49301077636.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/47833145991.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/34111168603.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/35591507690.pdfIn PDF document text
    • https://monyetmesum.com/contents/files/vemepuzajokivujanufepubem.pdfIn PDF document text
    • https://websbag.com/uploads/files/69075609754.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/80850246199.pdfIn PDF document text
    • https://www.wappa.com.au/siteadmin/ckfinder/userfiles/files/mebanuvesagojib.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/dagukirebavanoj.pdfIn PDF document text
    • http://4darchitecture.org/img/all/67000608686.pdfIn PDF document text
    • http://thebookmarkcafe.com/uploads/files/levalikesutiwenozu.pdfIn PDF document text
    • https://dehaventransportation.com/home/de/public_html/ckfinder/userfiles/files/jelagowewuxonaferofof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=duplicate+file+finder+open+sourcePDF link annotation
    • 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_off0000ef4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4A 10712 bytes
SHA-256: 2b60760a1fde2399acccf17408dc5ad91739f4c876e7756199bd11cbdf6463b4
font_01_sfnt_off00010807.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10807 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012019.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12019 19076 bytes
SHA-256: c1ea8592af8a1ad8fc2333f084f088622f27fa7046cc346335572e4477106cb5