Malicious PDF — malware analysis report

Static analysis result for SHA-256 a52f49cb185a718c…

MALICIOUS

PDF

88.6 KB Created: 2021-08-11 10:03:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4dca8bc269ed31a34e6930747e108f1c SHA-1: 47319ffdfb24cca87ed1f030d1236089c3b56466 SHA-256: a52f49cb185a718c3c6a49b8b6906d907948cbff3828b9ba8d389711b6d8078a
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, suggesting it's designed to redirect users to malicious sites. The document body was unreadable, but the heuristics strongly indicate a link farm used for phishing or malware distribution.

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
  • 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://allytemp.ru/uplcv?utm_term=can+covid+cause+vertigo+and+nausea PDF link annotation
    • https://abugfreemind.com/userfiles/file/dewopemoboneb.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608d28e6c07c9---15503186361.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/96459341018.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/10892768169.pdfIn PDF document text
    • https://perfecthospital.net/ckfinder/userfiles/files/81872290017.pdfIn PDF document text
    • http://citranco.com/users/files/dezalok.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/7146661730.pdfIn PDF document text
    • http://runningrhinelanderrabbitry.com/clients/875187/File/96516991932.pdfIn PDF document text
    • http://westtech1963.com/clients/d/d4/d4250bc21dcbbf02d7f9bc68df143add/File/2202986547.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160841afe91e2f---83182217534.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/950745944c5ec56e821a3fcb7572c627/wobexi.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc24406d36---6820412996.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160a88354f2add---dupoxo.pdfIn PDF document text
    • https://kingdomofgodmn.org/userfiles/files/bunukogit.pdfIn PDF document text
    • http://tonystelly.com/clients/873487/File/3029147227.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/22461781916.pdfIn PDF document text
    • http://geopraxis.it/userfiles/files/rezivebekomefegamuko.pdfIn PDF document text
    • http://extracam.es/app/webroot/arxius/file/57043050591.pdfIn PDF document text
    • https://cosplay-expo.it/ckfinder/userfiles/files/91739847246.pdfIn PDF document text
    • http://fittbike.hu/files/file/22745070769.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/4075992565.pdfIn PDF document text
    • https://balbok.net/admin/ckfinder/userfiles/files/negexowazilofik.pdfIn PDF document text
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/77078517201.pdfIn PDF document text
    • http://trevelsi.ru/ckfinder/userfiles/files/35535099221.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/2d4599aea8a247b131fe30a419ab47d2/jedeborazovorudujelu.pdfIn PDF document text
    • https://sinhadventure.com/uploads/file/72617906512.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_off0000f83a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83A 16760 bytes
SHA-256: 1559649d68cfe397b515816ff9ad95f07ba53141b46beb68c79af67316410fb4
font_01_sfnt_off00012401.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12401 10696 bytes
SHA-256: d353d3101b25aab5873f6ee8077dfc446f1ef4a826f1866c55d8c5daae40cc9b
font_02_sfnt_off00013c92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C92 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1