Malicious PDF — malware analysis report

Static analysis result for SHA-256 37b1e46a9edbd00c…

MALICIOUS

PDF

82.7 KB Created: 2021-09-07 09:05:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e9d40b4cca8c983dbc0b127949db170a SHA-1: cdab2aee9412af315c7386ca771f5c28371361a1 SHA-256: 37b1e46a9edbd00c9e3c42b61398527d7356a07588b6a6ff9d4e7dd0f7ee99f1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting. The embedded URLs suggest the document's primary purpose is to redirect users to external, potentially malicious, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://krisoc.ru/uplcv?utm_term=sunbeam+microwave+manual+sgb8901 PDF link annotation
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/ctbv6sq1otjbto1v9pce4lfou0/65663083098.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/2190aiq7ihgrbm71bd21aabp47/51525849220.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/40gffiou0s784uqs5b53bjqe0f/kagid.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/0hscad3cbb12sicfelnflogdsa/dorezaxanidoxepefenukoro.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3ecd6cda6---92957677414.pdfIn PDF document text
    • http://sunjewelsonline.com/userfiles/file/30961170448.pdfIn PDF document text
    • https://cafesca.info/ckfinder/userfiles/files/lowozofo.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608300c161f95---19142831864.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/86542865369.pdfIn PDF document text
    • http://abwmountvernon.com/uploads/files/buvelivotigozilotuvep.pdfIn PDF document text
    • https://noithatkuongthinh.com/uploads/files/pematajikivose.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/67468123660.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/77212123353.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/0edf92fb16029b38a5d4335857b4a48e/zesaxakulinexikuworiruxe.pdfIn PDF document text
    • http://khachsandomino.com/hinhanh_fckeditor/file/40039435356.pdfIn PDF document text
    • http://joyearland.com/ckfinder/userfiles/files/towimumajasasopiropuzotu.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/0c19a96d76296252ea9113d177af82fb/90806491873.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/82105338348.pdfIn PDF document text
    • http://pneusmarene.it/images/file/83255533198.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_off0000d95f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD95F 11492 bytes
SHA-256: f6c11ddca1ce7d72be0868090d8f85afd5e2332d04d2dcc5b84553248dfbd94d
font_01_sfnt_off0000f499.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF499 18744 bytes
SHA-256: 6515431d5a8eecaf46340360322505858cb6bd841fd04aa4afbcbfe0cc89c369
font_02_sfnt_off000125a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1