Malicious PDF — malware analysis report

Static analysis result for SHA-256 355e35d3820000ea…

MALICIOUS

PDF

86.4 KB Created: 2021-09-06 14:31:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7f1d73204712a595dcde190181250c86 SHA-1: 0ddafd078bb6f0151e32ff0565cab4ee75a7a8ce SHA-256: 355e35d3820000ea228e5ca89746ca2f523ed9df775e6101a4625385ca6ad561
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a malicious PDF that utilizes a link farm strategy, directing users to various websites, some of which are hosted on compromised WordPress installations. The heuristic firings indicate a phishing and link farm pattern, with ClamAV explicitly identifying it as Pdf.Phishing.Trojan. The embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect users to malicious or phishing sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://philabc.ru/uplcv?utm_term=tratamiento+del+glaucoma+agudo+pdf PDF link annotation
    • https://tssch.in/tssch/application/admin/uploads/file/6725209573.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160982a21cbbd2---junutenonamezixel.pdfIn PDF document text
    • http://bbfederico2.net/userfiles/file/wuxatesewelasozepu.pdfIn PDF document text
    • http://studiolegalebisantis.it/userfiles/files/telarukenex.pdfIn PDF document text
    • http://mhs69indians.com/clients/864804/File/pifikura.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/tedetutejoleninudedogapu.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d83a5e90f9---32564388768.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/kafabewikijomifuwolufib.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/12gbq0m4o0p107ov1i8bhsujo5/87322007316.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/48962005080.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160fc739fb7cd7---nilusalunuxewefaz.pdfIn PDF document text
    • http://aokunoil.com/ckfinder/userfiles/files/31778126874.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c88a3a60ff7---sexuloloketoluxedidixif.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c1220798584---56941884515.pdfIn PDF document text
    • http://casaledellasignora.it/userfiles/files/77927971877.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609272c2d2675---waxazafuxijuwawomuleru.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/225b4e880bb73d49c256fecfc0183a8c/fuvifalarax.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ec5b24f0b4---waluresojawelila.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/16790578077.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/leramelevibojubaxifovuk.pdfIn PDF document text
    • http://szwygs.com/upload/rupenolotoxefaxotidonufir.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/duzelenedafuregojeta.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_off0000e830.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE830 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010047.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10047 10860 bytes
SHA-256: e0e111b241fca7515ea326f922843365559360114676eb449e3cbe53343ff376
font_02_sfnt_off00011919.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11919 19960 bytes
SHA-256: a49ad880565e95f82033b9a4ea12916d4b3995bcdfdc4a8e22cf6b3fd8a6d68c