Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1a6a90bb298569d…

MALICIOUS

PDF

75.3 KB Created: 2021-06-24 04:09:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 7da482fa7ac8726ee0eadd352a338aed SHA-1: 0eb6f4b553957462c7e6141a4b877474f134c8b4 SHA-256: a1a6a90bb298569d9c8dd87d4368b148e6ed6fc45d80709d61f97bc97b1da88b
156 Risk Score

Malware Insights

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

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 0.9998

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 https://upchealth.net/wp-content/plugins/super-forms/uploads/php/files/7c01995a40d8bcaf9f776f9b87861273/23982809922.pdf In PDF document text
    • http://dzstock.com/Upfiles/file/vakojusupex.pdfIn PDF document text
    • https://radmangroup-ye.com/rgfiles/file/xatitapinebabu.pdfIn PDF document text
    • http://alliance-ltd.com/userfiles/lezewusarolagapuzazijotuw.pdfIn PDF document text
    • http://benjamin1908.com/clients/f/f4/f4560e3fe432b95d15e234f900dec36a/File/zofewoj.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/gnhf3kbl8c077ksgb0q3t1jno6/mebat.pdfIn PDF document text
    • https://cdpu.net/wp-content/plugins/super-forms/uploads/php/files/c4a98708a574823672ecf5611a03d1b6/13940211657.pdfIn PDF document text
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/b77163d3d0c60e9b05d1febd87ad51a2/mepupexorawitenuxezufozop.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/texipagireto.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16070b14f4ed09---7109199694.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/gupaxubekewuwubasokowab.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b8e786e6aa8---59015249907.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16073dbdd579d4---14700574532.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed72e6f087---53292649886.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=valor+absoluto+de+0PDF 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://scripts.sil.org/OFLIn 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_off0000d14e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD14E 5064 bytes
SHA-256: 24f72b38cfd73e32889c335138fad03b6a22ce0730cd1d996d79860e17c1ea19
font_01_sfnt_off0000e28e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE28E 12784 bytes
SHA-256: 205e1b04e1f82d293299f9bf38ec0f0d69d2e8c57cc42cfbb530865533d884c0
font_02_sfnt_off00010a1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A1F 16060 bytes
SHA-256: eccb4a4e23ec17ef3ae34a7e59b2b3ca0bade477786653c37f50dbc176102729