Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cb5ec71eb094033…

MALICIOUS

PDF

105.1 KB Created: 2021-07-05 11:06:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 2fcda3fc6e5e953cbeb515d386119596 SHA-1: a696640c7f6154a799643125f7bd384e4129ac9f SHA-256: 4cb5ec71eb0940338eaa0293680fd5cc43254f5f034f7d680f9fba6e92822432
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/f34e9b9005731d04ac21cbd192ee04f8/43150405833.pdf In PDF document text
    • https://publicbridge.pl/userfiles/file/vuralaluvupoxopikibure.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c27476c7106---53430828277.pdfIn PDF document text
    • http://sunjewelsonline.com/userfiles/file/50394990653.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/f7059109b94521e8d3c02058c5643dc9/96402955271.pdfIn PDF document text
    • https://balbok.net/admin/ckfinder/userfiles/files/91041417228.pdfIn PDF document text
    • http://nw-line.ru/generic/uploaded/22477020708.pdfIn PDF document text
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/74987720058.pdfIn PDF document text
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/maijeut9sdbhjf6qtvfaiuauaf/35209036068.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc6f9cf3a81---wusefuzopivoba.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f58b047af4---20835626123.pdfIn PDF document text
    • https://unibel.pl/pliki/upload/file/kuribiwekaxelufakufesa.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/22840483242.pdfIn PDF document text
    • http://daydala.com/userfiles/file/vorepuz.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/furediv.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160760874ea810---kajijuzafoxukudux.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/74e4f0682ad34592dc24727bf05b2a59/dupiwazi.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a954aca64d4---59850336617.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=sample+letter+waiver+of+penalty+for+reasonable+causePDF 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://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_off00013222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13222 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00014a34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A34 19336 bytes
SHA-256: cfaea0daae4d28e2fb7b4908f9eff165f57e3a5da0d46dc95798e5a63bc645c7
font_02_sfnt_off00017ceb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17CEB 11220 bytes
SHA-256: 8d02f94a37ac3a8ee9be699abfd65754dfe9928fdd1dc09b62b70e63bb53c784