Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f7beaa94fd174c6…

MALICIOUS

PDF

82.2 KB Created: 2021-09-20 00:42:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6d6f44868f0a5a69e21f5bcc43088d9c SHA-1: de486ca4593e629fb90b04c32a97804555594160 SHA-256: 7f7beaa94fd174c66940c51a7c57c6b0634678894c925d3e1fc18fdb8713edba
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Numerous heuristics indicate the PDF functions as a link farm, directing users to various compromised or disposable hosting sites, some of which are associated with WordPress uploads. The embedded URLs suggest an attempt to lure users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://ketchas.ru/uplcv?utm_term=android+music+player+with+crossfade PDF link annotation
    • http://guanzhuli.com/userfiles/file/63246014367.pdfIn PDF document text
    • http://bangladeshceramicsociety.com/uploads/editor/files/zerofafivufopa.pdfIn PDF document text
    • http://tincorner.vn/uploads/files/14330959701.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/36639267244.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/jogaridumevelefijovekubep.pdfIn PDF document text
    • http://vizcsap.hu/files/file/miweloxejaliwixe.pdfIn PDF document text
    • http://daoltrading.com/userData/board/file/55400157711.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613d8b0bca760---73475415647.pdfIn PDF document text
    • http://atsolution.org/userfiles/file/20210913214431696530151.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/f29c58d58a546d3a264add071961aadb/92250362624.pdfIn PDF document text
    • https://implantologie-deva.ro/app/webroot/files/userfiles/files/25906364306.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///31800091367.pdfIn PDF document text
    • https://hotararicedo.ro/files/files/81449454171.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/borumikizivemowafivov.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/diwodasuxesujana.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/781378b7bf17e00522e823776dd0ac87/3607138144.pdfIn PDF document text
    • http://oletrans.sk/editor_uploads/files/90120021251.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147a4eceff65---dogikojonijesebedalaz.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/116fb98da9759cc2993ecd3c2a3d8a6d/59259923800.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/77410654735.pdfIn PDF document text
    • http://www.horakgolf.cz/ckfinder/userfiles/files/39581982466.pdfIn PDF document text
    • https://www.tocbirsen.org.tr/ckfinder/userfiles/files/94029161283.pdfIn 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://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_off0000dc14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC14 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f426.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF426 17252 bytes
SHA-256: 25b97b71b0fa134429020681c37d1112e9b83ff6d322c8ee56ff0dfb7512fda1
font_02_sfnt_off000120f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120F0 11164 bytes
SHA-256: d92b2e7b10971f11bbafde1737b66e9b846e74d4df4548b921eae3dd321fc689