Malicious PDF — malware analysis report

Static analysis result for SHA-256 b73919251a84cb46…

MALICIOUS

PDF

81.0 KB Created: 2021-09-11 16:03:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: cb8ebfe088f869a5b8f5536b0a4eb685 SHA-1: 18ca99826ee805b6ecb53835b68608d6d7b18b75 SHA-256: b73919251a84cb46f7afe66910c47c4466926f4369df69ccb15af5239356468f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest this document is part of a phishing or malware distribution campaign, likely leveraging spearphishing attachments as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b952930e98---97794110999.pdf In PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/pufupojaxifedapiz.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/81567434710.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/84117751131.pdfIn PDF document text
    • https://sma-dfgg.org/site/admin/file/datudujosodaxetafibadezi.pdfIn PDF document text
    • http://ozhelalikram.de/resimler/files/80506225584.pdfIn PDF document text
    • http://feynburg-uhren.de/uploads/66371212275.pdfIn PDF document text
    • https://ysh.my/userfiles/file/50339018915.pdfIn PDF document text
    • https://epagneuls-bretons.fr/caningest/images/file/wajopotodinefujoje.pdfIn PDF document text
    • https://euroroma-bg.org/files/file/88397785463.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/658058093.pdfIn PDF document text
    • http://camdohungdung.com/upload/files/96161053375.pdfIn PDF document text
    • http://agenziaimmobiliarecannavo.eu/userfiles/files/29414306500.pdfIn PDF document text
    • https://anbuadidravidarmatrimony.com/ckfinder/userfiles/files/nesikagerapugigawurew.pdfIn PDF document text
    • https://eniedu.com/data/file/20210910030703.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/damovikawiwusagonukub.pdfIn PDF document text
    • https://www.loisirs-auto-occasion.fr/ckfinder/userfiles/files/33959772315.pdfIn PDF document text
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/judixisuxerajuwevo.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/48880791596.pdfIn PDF document text
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/36e899ed3170ee85e133cb3b74c68287/88128992574.pdfIn PDF document text
    • https://8foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/donukesiwazukixisal.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/juwinipusaxuzurobuk.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/14352363344.pdfIn PDF document text
    • http://bolt-go77.com/fckeditor/userfiles/file/36244647086.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1613976ce1122c---42021335810.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=android+construction+calculatorPDF 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_off0000d8b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0CC 10312 bytes
SHA-256: 922dd20acc521542bcee997edf781e3789e503b22e74961553bc0fb20f4ed4ce
font_02_sfnt_off00010826.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10826 18044 bytes
SHA-256: 393f3a3292a8a550d88cc8a21845f0aed1960eb7755a9013e6c6556807e5c7b6