Malicious PDF — malware analysis report

Static analysis result for SHA-256 12a5823bb0e9bb36…

MALICIOUS

PDF

80.4 KB Created: 2021-09-03 12:44:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6da3953ae66a4fae3991cdebd1d6dd90 SHA-1: 5ba11c522cd3809d0b7e30059735763a0eb84e45 SHA-256: 12a5823bb0e9bb36bacc15cd4da73dbce9877eb8d634bb99ce08c2f0865b62cb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links 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 indicate an attempt to direct users to external, potentially harmful, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://chcial.ru/uplcv?utm_term=disciplinary+procedure+forms+pdf PDF link annotation
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/mraojpo07pbottmke76etv9tlt/36302904106.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/edfc95e7e2e81173f6c6be5685f201a5/zagezinepakakufi.pdfIn PDF document text
    • http://impactmediaresources.com/userfiles/file/7773464834.pdfIn PDF document text
    • http://veszpremlizards.hu/_user/file/bobazobidurutolafuw.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c44f2ee8b75---40085819740.pdfIn PDF document text
    • http://lukoilmarine.com/ckfinder/userfiles/files/37761485712.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/iq23bg2q9hsvqecgq0rouqenre/79795949274.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b55c2617a2a---bonedofetaga.pdfIn PDF document text
    • http://alaskacounseling.org/clients/8/87/870ae3779d21e956d596131c1dd113ff/File/gokufepikosufug.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/runabek.pdfIn PDF document text
    • http://www.alcera.ca/userfiles/file/53202601619.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/2ba493246a9073d96ab41e6498015238/meresemumirovogevazofasit.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/5ab64f5c1a5ddb8be48d0b874436660b/wubixapilorelefujatakevev.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/8885da4f378e4e21ca246daa4f935c6f/vuwutilusaj.pdfIn PDF document text
    • http://reelproductionshd.com/userfiles/file/77444753336.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf00d68f6a---dijodawati.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160955cf2d2da3---48383971613.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents//files/vimorizigidopidifalewufat.pdfIn PDF document text
    • http://antansconstructions.com/ckfinder/userfiles/files/23579993118.pdfIn PDF document text
    • https://webmenuplus.com/images/file/midemidonowixifexamukano.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/9254c19c36543c8654954af6714b17d4/jepowovavufurokusutezufob.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/purujemeromogo.pdfIn PDF document text
    • https://steammining.com/userfiles/file/mobozixajal.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_off0000d930.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD930 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f147.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF147 10900 bytes
SHA-256: 19c6a37a3f8557e787847e68005e7659652a20dff2282fd465d8d6b844541420
font_02_sfnt_off00010a74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A74 16224 bytes
SHA-256: 6b20a7169fc57bd70f487950b9a3887de97653bcb67e118299e76d64fa7b324e