Malicious PDF — malware analysis report

Static analysis result for SHA-256 686113138e79a4a4…

MALICIOUS

PDF

73.6 KB Created: 2021-06-11 01:54:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 1fc992a42d101dbd973d0655e741b818 SHA-1: e1cedcc85af8ae6fc7e946d92de52c06618bcf76 SHA-256: 686113138e79a4a4dcc19cf543954622793f9ed9732c7474c9827d897b990aad
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress upload directories, suggesting a phishing or malware distribution scheme. The embedded URLs and link farm heuristics indicate the primary goal is to redirect users to external, potentially malicious websites.

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://crysiq.ru/uplcv?utm_term=example+of+a+teacher+cv PDF link annotation
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609069759aea6---4244753447.pdfIn PDF document text
    • http://mppscstudy.com/admin/usercontent/file/56659214242.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/5ne2kpsgfb1ku89lrejklle4i9/50657632423.pdfIn PDF document text
    • https://ensasoft.com.tr/wp-content/plugins/super-forms/uploads/php/files/77h6hj799njdk97eve167v42lr/22894651103.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9d1642b715---72915393995.pdfIn PDF document text
    • http://rolmech-strzelno.pl/Upload/file/boxoxedela.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/21672426319.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/kukc049o3l9np6u7lsuk6q49l0/77214045410.pdfIn PDF document text
    • http://chono.mn/uploads/userfiles/files/mubipof.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a021bb912e---34302213076.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/21b962f5625eeec8d6e040cd31d79612/15918710696.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608556627d649---94650935847.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/60b16eb205537cbe005951e1197a3669/25769679885.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/2b0ecf51491edaa261e524a6adf53228/61063815475.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_off0000e3aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3AA 5164 bytes
SHA-256: d58093e7bb7a231f203c48e1a3b1bb0cd86521a197aff9a56fe697f795d274dc
font_01_sfnt_off0000f51c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF51C 10960 bytes
SHA-256: 614a74a1a9f89a25c884a179acb7450ed89f959bef31f445ccdf294848c00286