Malicious PDF — malware analysis report

Static analysis result for SHA-256 6350bd7398f3aa2e…

MALICIOUS

PDF

82.2 KB Created: 2021-06-25 17:48:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 97c3a02e3abe2fb0be8a4f5aea5b5e4c SHA-1: fb7b35c33462ab19138493fbbb588f19b1f36aff SHA-256: 6350bd7398f3aa2e87568c957e4ffe014e9ad3abcb2f2fd0798c947ead494ad2
156 Risk Score

Malware Insights

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

The PDF 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 upload directories. The document body is heavily obfuscated, but the presence of multiple links suggests an attempt to redirect users to potentially harmful websites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9719

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 http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ad2425872---35403789562.pdf In PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d093b541c47---savimorogefulepegusidexiz.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf9007a093---duzexufadoxiwusegi.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160963e860551d---vinivi.pdfIn PDF document text
    • https://infiniteprospects.com/FCKeditor/file/gurufusujezinijet.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070b4c316e27---3855690263.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7cc95a25b---pejanatuseselozorefer.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/fa9715f39b2e955bc3894d426101141d/ruligudoruwomojokenalexe.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/9b1a0f94be657ec64fa2720a75b7daa7/764368646.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/rimap.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/75quumhuc4nv76uj00upbi8u04/sevujizevaseg.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609887721e4ee---63716950574.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/28262553811.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbec51ac383---sugetil.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6260be6c2a---36349187815.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a310107bc40---rolobobodukubiwunuvuja.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b2029e5ec23---98784642950.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae244e58a4---ginigoxovirotaz.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160867e1850015---rorevimubawiw.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a623a175e0e---kuwudupukulogubamop.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/37edbe067cd624137a915e5770536186/74897895237.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/qegesap11hgt9g13crtvau9n24/42870931994.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/29880866237.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/zasuxukoxajobakad.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad5e8c6ec9f.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/20590654738.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16072c12fe73e8---79243266420.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/vopalafise.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=guess+the+stray+kids+memberPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3CF 10728 bytes
SHA-256: 70868da9b9a181f7c2fe91d1c7fbd93c0123783597283fbd2e3ef971d094df3d
font_01_sfnt_off0000dc8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC8A 16712 bytes
SHA-256: 21e8ebc2967b583b0b4ced7471dd10ed59ae433b31fe71c8d8e8d73585abbe55
font_02_sfnt_off00010855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10855 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00012066.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12066 17112 bytes
SHA-256: 885b9024a80bd539ee88f4c17c1e1fa3cc6dab475ff5b740ebf17c73a317c9ed