Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac27d113a11c4f22…

MALICIOUS

PDF

79.6 KB Created: 2021-04-28 07:22:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e6f44f85db8c03cf4c9b11c733010708 SHA-1: 22928ead13d8d70c4866015097d1621d32fe1baf SHA-256: ac27d113a11c4f22fff487a80ce81f90f809c77d8462bff25c33f22cceedee7e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains numerous URLs pointing to compromised WordPress sites, suggesting it is part of a link farm designed to distribute malware or facilitate phishing. Although no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest it is intended to redirect users to malicious content, likely as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9a0d7a05a---26469431365.pdf
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160862fdb631ec---80617447104.pdf
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e57f148d35---72570613856.pdf
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/g6keegcpm3t97472sq4hm4fbsu/50516946561.pdf
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/48a6203487736303436bbce3ab5938a2/36082769904.pdf
    • http://alarcon-v.com/editor_upload_image/file/pepujatalisofaz.pdf
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/df20f71439744c6ec32e1dea89c52114/90796315461.pdf
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/d674a0364a9457bfabfab2e2e0f4d22a/20724772790.pdf
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/k0k0ss55jsgdunm1cg8mnjs4gp/18737876634.pdf
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/564b3497fd95087fac6910f526c8b17f/86768702615.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160887d080f0c4---73574439827.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/3sqp7bbfteipgv05c9a6f36ab0/265342605.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/i39ardahr5ghs5ul7lrmb26ifs/zalugixonakibaxifusoker.pdf
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/bb6a45jp0pml3cksiq054atrlf/66190061871.pdf
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cef73020ee---1037328581.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=corporate+brochure+pdf+template
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fc15.bin
10d59fbb3c52d7b7dc91253342272571c2e599efdd395b41403f3266ab2b1289
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC15 5260 bytes
font_01_sfnt_off00010dc2.bin
d86374501c2ad614042d14c6722adb8b3511ab8ae9e2c78e6b82608c4bc43f6a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DC2 10460 bytes