Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee625c62c36ce39a…

MALICIOUS

PDF

77.4 KB Created: 2021-08-14 09:17:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 23c95a2c1443266687eedc1d3a273101 SHA-1: d9fcd536f93e251b839c921835aae2dff34ee4b4 SHA-256: ee625c62c36ce39a2aa80514f4294e08e08d3f27839afc5c91fc1cf7557c496a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised WordPress sites or link farms, suggesting an attempt to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the URLs and the heuristic firings strongly indicate a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crewmak.ru/uplcv?utm_term=finding+perimeter+of+compound+shapes+worksheet PDF link annotation
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/fp48cho8m6pa7gcf94fjqrhhie/90930503839.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/66cia5rrah24n1ooeqj350rj6b/lefamebapewamofugirin.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/k2a2880h3g7qq0jr9o2a22j62p/90051397398.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe0cbd2eff---4340616834.pdfIn PDF document text
    • http://xn--o79av69abka850ab6c.com/upload/file/202108140707212960.pdfIn PDF document text
    • http://ff-engineering.com/userfiles/files/37226519254.pdfIn PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/xazefuzurixuneduxa.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/52i5k4ap4m8krm336c0pfver1g/joboxinepivamexoxoxi.pdfIn PDF document text
    • http://plafondchauffant.fr//img/user/file/zefezukoronivixeg.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d67e73757a2---nasakeso.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160acdae140a9f---sakefaroripijibakubutag.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/16102d6040bccb---welutokopibemudur.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/7089481cb4f8da4e2d5b5203d07a62fe/39073861403.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d482ca1703---tunopo.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7da29136d---jukijepuni.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/30667103909.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_off0000cb31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB31 16232 bytes
SHA-256: 794c0fe2075e1ae1bd2d2d7a550a8b69780f1e0b20436df8ad4a7fe9c4c5292a
font_01_sfnt_off0000f4f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F1 11276 bytes
SHA-256: 8fde1af9aa7c5f22c5b5e7cd1f04ea5152efec828a1d9646aee867fe274d36d4
font_02_sfnt_off00010f16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F16 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1