Malicious PDF — malware analysis report

Static analysis result for SHA-256 08f07752d6954f18…

MALICIOUS

PDF

88.5 KB Created: 2021-06-25 19:18:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 2380fe5d3e6b80539c75af9e3b9845f2 SHA-1: c1fd88390c4bab47fe671e6a08e5bd0d16c89e80 SHA-256: 08f07752d6954f18024bf86651fe2c5b4c88703a07be00240c2a796e0a5c2430
156 Risk Score

Malware Insights

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

The sample is a PDF identified as malicious by ClamAV and an ML classifier. It functions as a link farm, directing users to numerous external URLs, some hosted on compromised WordPress sites. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a deliberate attempt to distribute links through potentially compromised infrastructure. The document body is unreadable, but the overall structure and URL distribution suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/5876074ca4854c091c53119774dc370d/5614270205.pdf In PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/72190057268.pdfIn PDF document text
    • http://thangmayedex.com/webroot/img/files/63301523151.pdfIn PDF document text
    • http://ptairsupply.com/userfiles/file/86986447494.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/9p9d3vcsafqkfmmmkkjrqvjchj/21875242641.pdfIn PDF document text
    • http://russkiivopros.com/images/FCKeditor/file/87579808608.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/5135e751deb7973149d17e1603bdf0ef/bizesoravejerutodiboj.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/26232444120.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//didolilowiviwebekeb.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/66a4397262d8a82b63380aca956d1d66/linutup.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/zatesetazupuxikik.pdfIn PDF document text
    • https://observatoire-omic.org/documents/file/tosizezuneta.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160879e1fd18c8---taxuroranikor.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b28477172dc---palotizonopudoxojojobufu.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/ca6260536bea97712b3e936e4eb09f21/46486504585.pdfIn PDF document text
    • https://nbtele.com/en/cache/fck_files/file/65039561413.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b38d37b94a1---58409309137.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8143533a5b235c0090f4658ef5e91189/90134453396.pdfIn PDF document text
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4d95d255b---66473453583.pdfIn PDF document text
    • https://taevlingar.se/images/pages/file/94299480831.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/12305826692.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/92302951634.pdfIn PDF document text
    • http://dfh-consulting.com/userfiles/file/13280706369.pdfIn PDF document text
    • https://systematix.pl/userfiles/file/kulipujotalododikofada.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ba5bc4acd1e---wobevezepew.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/965ef41293fbac76ebc9630a8cbd58d1/5883237770.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/7c002c6987a0c6ddd81e84895c74653b/bazixe.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160aba718b0a68---19377209842.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=sherry+turkle+the+second+selfPDF 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_off0000f464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF464 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C76 18164 bytes
SHA-256: 6766db976b99e7a72d5bf8d9655c4f30d5c4927e31347c59ad7dc81b63de7a5a
font_02_sfnt_off00013c15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C15 10700 bytes
SHA-256: db873a0055144339414b94eee5ca905e6b55c24a9be67bab3d6418fa4714c401