Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5a81961f8099b12…

MALICIOUS

PDF

76.1 KB Created: 2021-05-30 12:18:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 1c5bfba3b548ab95e5a025610a317c1f SHA-1: 2bd50f1bf85e7afd1dc28d6b4e5798703f8bad6a SHA-256: d5a81961f8099b1250192b30bc434e7a5dbe15d19085ee52cf90feb23c51388c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised WordPress sites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary attack pattern involves directing users to these compromised sites, likely for phishing or to download further malicious content.

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://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16099739fc763b---nekapewakopubigexa.pdf In PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/402d7055f519d15341a57f08c88f3fee/10644390189.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160905812e56ea---60476101944.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/39187578343.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/25d94c0c369d66efaebbb0defaafae27/86284758595.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b339125af83---rovesaxenenuginigowu.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/d6592bcd5fe89900b084527ce4d273fc/27996817181.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/gufomipiguzukola.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9323d0d1ec---gubiwu.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d28279e369---91652931540.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/cbd19a270ca17d6cc56a55e63ae86dea/wumedesoxolitamugusizan.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d2e5098e1b---sewedukevas.pdfIn PDF document text
    • https://alice-immo.com/userfiles/file/94107725309.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/hmm5kukiq43g4ms3sjn5t5c3i5/dofijapepilulipipituvu.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/6a48d46be4272955a16fc81b3ad8c790/juzut.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c25b1d729a---wimepojupipeg.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/YTWXjIUwRh0/uplcv?utm_term=ayreon+the+source+booklet+pdf+servicePDF 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ebf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF6 5388 bytes
SHA-256: d08119b8310e976f5c9ae2c79b75a519f5e73331de706a20e313e8378befc296
font_01_sfnt_off0000fe59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE59 10684 bytes
SHA-256: 3dd62defad7f7492cb53dbcb3c20892ddbf471e52c63b95615a4eac48b36172a