Malicious PDF — malware analysis report

Static analysis result for SHA-256 81f2f0883b039d98…

MALICIOUS

PDF

75.8 KB Created: 2021-06-24 16:52:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 4d9427b57d1a5de411072f36f004b310 SHA-1: 356b30f887e019a35ce9c2ed9aabc6b3729d9acd SHA-256: 81f2f0883b039d98ac1d116173a1d7af52e25d13768fe5626e989b41207b643c
156 Risk Score

Malware Insights

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

The PDF document contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

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 https://laborke.ru/uplcv?utm_term=top+10+pdf+converter+software PDF link annotation
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/2b205f9f773f2bf436edd6709d273e78/feguna.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7d55ecd2c---96419130010.pdfIn PDF document text
    • http://benevolo.it/userfiles/files/dumedawiwigi.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/e1cac857359873a0e409b1a489cbfc20/70631309676.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160abdfeaea257---95863784078.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/38334506694.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d20cc9c0c76---10046146568.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/20s372q57emiqv7lukcdm1k5h4/sogenumakirezi.pdfIn PDF document text
    • http://thehigh86.com/clients/13680/File/bunil.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcff74ae724---tunafenenaxasebo.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861b1935d7f---78267527245.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606eeeddade84---saxirilaruwo.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/sohqnjpvq6jtua3k4ppdcml7ag/giked.pdfIn PDF document text
    • http://elyriahigh1974.org/clients/0/05/052ab20d644b737728595af1a47b4450/File/59346625456.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607422cccb90e---29733252940.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba442b9028---67380466254.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B9 5412 bytes
SHA-256: 1d48f73b78ba63b6ea346b8a14672dd21a4dcf86bf1969c251f422072c3f3051
font_01_sfnt_off0000fb54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB54 10916 bytes
SHA-256: 62a49d6968463728bd1d251c1ad697364bc0efd44e1d762d19471146972eb608