Malicious PDF — malware analysis report

Static analysis result for SHA-256 54cdbdc62179cb91…

MALICIOUS

PDF

79.9 KB Created: 2021-09-07 22:50:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: a2d08dfc64adcfb7a9ce9fa1b5bc72e3 SHA-1: 8f4f5fb09861dbb13698a71e525d33f36f6112cd SHA-256: 54cdbdc62179cb915e518008f59a178d10a7b126d7157a323f3ec0264d7b47ca
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/8238a0a5fd28dcfe1d0de4cc477e0dc0/nerumexelusotejomifuvon.pdf In PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612995f7ca901---33740565915.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/5e1b59c5d344d91cdecc4249b4716960/70235392014.pdfIn PDF document text
    • http://irths.com/upload_files/files/63923376055.pdfIn PDF document text
    • http://solyaris.pro/admin/ckfinder/userfiles/files/51403977249.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160857b5186c0b---23996290214.pdfIn PDF document text
    • http://e-hematologica.pl/users/file/53431866365.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606c83363a2ee---rumomuxonevigopa.pdfIn PDF document text
    • http://x04ydivan.ru/userfiles/file/juvorexun.pdfIn PDF document text
    • http://novo-foto.ru/ckfinder/userfiles/files/jalisusalizade.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/fesaw.pdfIn PDF document text
    • http://duonglaohanoi.com/userfiles/file/lesarogamibewusedewuwun.pdfIn PDF document text
    • http://heureka-cz.eu/files/mewawat.pdfIn PDF document text
    • https://peisheng.org/uploads/ckfiles/files/612f8642b95ca.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/97732929635.pdfIn PDF document text
    • https://livre-d-art.com/ckfinder/userfiles/files/84309877482.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/07/202107271100154390.pdfIn PDF document text
    • https://editionsitaliques.com/userfiles/file/10006997747.pdfIn PDF document text
    • https://mamo-tato.ro/userfiles/file/rademit.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c6d3ac5ea20---59266394742.pdfIn PDF document text
    • http://groupkaishan.com/d/files/42369912549.pdfIn PDF document text
    • http://elyriahigh1974.org/clients/0/05/052ab20d644b737728595af1a47b4450/File/88815579020.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=how+to+write+a+formal+letter+pdfPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d62f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD62F 17276 bytes
SHA-256: f3a24774e9ed93810691bd25bb7a66ae2e656cb4dbf21729f451e2c38f76cc96
font_01_sfnt_off000102b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102B3 10464 bytes
SHA-256: 468b2122ceab689e5a91bfbab074448da479e86eadfd3ffac03745e1f61c3295
font_02_sfnt_off00011a75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1