Malicious PDF — malware analysis report

Static analysis result for SHA-256 23c5aaaf97ce7efa…

MALICIOUS

PDF

72.1 KB Created: 2021-06-21 11:52:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 8772651380e7d9505028c04d03ae9c60 SHA-1: 6bbe4f8c4ecb0ee912f203dc661aa1cad9f28c82 SHA-256: 23c5aaaf97ce7efad282d4ec9dff9fda7e8f0f549bf35496efebba07945ba741
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://infrive.ru/uplcv?utm_term=3ds+max+2015+keygen PDF link annotation
    • http://urbancollab.com/userfiles/Proj_Name//files/dezepamulekikewazufemil.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/c25fbe893150a6ba4e68515e49ed643d/tilowerowa.pdfIn PDF document text
    • http://krzysztofmalec.pl/gfx/fck/file/zapudizusenokumopinof.pdfIn PDF document text
    • http://salkim.com/userfiles/file/bewusonisugiro.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/3bd2e97db4eeb18539d2b6575bb07237/retes.pdfIn PDF document text
    • http://ivepe-elearning.gr/assets/UserFiles/mainHome/file/4790835476.pdfIn PDF document text
    • http://gapoom.com/upload/fckeditor/file/gavidutibujorus.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/6821b0a4732d4366215a2a032703761d/34435089706.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec5cb51f88---vibonikewuramegutifiviwu.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160809758e6918---53651490020.pdfIn PDF document text
    • http://bmsorganica.com/userfiles/file/xoboleloxirelowo.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075ff1a23c88---63179777840.pdfIn PDF document text
    • http://ilkyoukais.com/Images/Media/files/16889345600.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160781d1aae4ff---dupesejutiruvifetageda.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/48568c70f0279637b81b4576658b874b/jinenuxevatogofexunemeta.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/8uilic428jvafqis87i856r6ag/74705690535.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608329aa22398---seguriluvovukelovobetakum.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA9D 5772 bytes
SHA-256: fed3e46c78fda115059a920678182154cc8b199d103395d6f0f7af777276ebe0
font_01_sfnt_off0000ee46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE46 11368 bytes
SHA-256: 569d95fffffe9a0ee86d9dca047662402b1fab75166d649c8538446a48b79401