Malicious PDF — malware analysis report

Static analysis result for SHA-256 03894f558191e484…

MALICIOUS

PDF

75.2 KB Created: 2021-06-18 12:05:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 0668d318750a2e8ba7fa17fc5a127e7b SHA-1: dba3f79034b6744dda3e556c99b4a8a299de9cc0 SHA-256: 03894f558191e484f049f4dce286cc28fc1f4f9a17130089794507a6a8c9b0d0
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous compromised WordPress sites and disposable hosting domains, likely as part of a phishing or malware distribution scheme. The document body, though partially corrupted, suggests a lure related to 'chromosomal diseases' to mask the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://pwr-tech.ru/userfiles/file/lawugadixaduvimisezimofes.pdf In PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e782583f2---11439011771.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608828f25797d---xudukizivosowabadozefaxuz.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3f0c5b7885---nanitutabifubajowa.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e6bfc1fea4---8946979589.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/2c97847afe617076bf0631397a7ea52b/17426634054.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/sikejovujeziponudepamu.pdfIn PDF document text
    • https://noddy.nu/images/file/mebam.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d6325a3c18---kijeluf.pdfIn PDF document text
    • http://backyardreleaf.ca/clients/6/6a/6a4eaaf8452764cb6fc14c9064ed0c71/File/11485003074.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609e73a7586a8---16224181855.pdfIn PDF document text
    • http://ipceurope.com/assets/file/97531468502.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078c8165ab5a---95004862666.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/42f6od758aqnn281vonajd8ldv/50891457035.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afcdcb42961---jafodagaxuxadupuper.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/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=general+causes+of+chromosomal+diseasesPDF 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_off0000d3c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3C2 5292 bytes
SHA-256: 48303c81615d28e5d98ad5b11503eb1f1563b7a33f829cc91a19cbce5371897a
font_01_sfnt_off0000e595.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE595 10732 bytes
SHA-256: 681d6573ba924a3c2ced2e7f8de46265f2793e1ff17e7a699bfef6220bdcf2e1
font_02_sfnt_off00010a98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A98 16092 bytes
SHA-256: cee1080d7bf7b1403f8248aefffbfaa95a5b761b99ee9843b2d0716478a5e436