Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1c0d9156d67fd4f…

MALICIOUS

PDF

84.2 KB Created: 2021-06-20 15:08:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 083a22d229a507bdf909fdf4228bbad5 SHA-1: 471e95214cf0dea41940169e9e1533c2349ac550 SHA-256: a1c0d9156d67fd4f211da78d2c4dcc9dc738d87bfc051095bdee37daf7baad09
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate malicious intent, flagging the PDF as a phishing trojan. The document contains a link farm pointing to compromised WordPress upload storage, suggesting it's designed to redirect users to malicious content or download further payloads. The presence of multiple unknown URLs hosted on various domains reinforces the phishing and potential malware distribution vector.

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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b800a58a58d---39690638967.pdf In PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1609692396a229---53902922140.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/74893b1770ad215472e67e7462d2cd30/45182695756.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/6124a974b16a6d1354018c4ae992aa0f/wovirokekapam.pdfIn PDF document text
    • http://rollfactorytogo.com/uploads/files/bupivigareruw.pdfIn PDF document text
    • http://dnepropress.net/files/file/kijutijadinawixixajupek.pdfIn PDF document text
    • https://bodegoncriollo.com/userfiles/file/nidimexufigikof.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160850e13cabb4---12596844173.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160919c015d6c2---nemizesubo.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/f03aa60e98a1da71988b054c514a016b/vizixijopekipopivenobas.pdfIn PDF document text
    • http://maristaslardero.es/userfiles/file/32881258670.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5bc581014---58877757083.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/16097446ab9e5b---88357363328.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc918e8e1e---begipolefuj.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bca4e65e045---mowowe.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c15027aa3ef---domeruw.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/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=valency+of+all+118+elements+pdfPDF 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_off00010619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10619 5516 bytes
SHA-256: e35f4df01247e41abd9e439c3dd8b4d6ccd16823777121b141230f85fd8c90fc
font_01_sfnt_off000118e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118E6 12184 bytes
SHA-256: 8f888afb60b51d6f738adcb2dadf948cd022820f577522658ed6222df90da804