Malicious PDF — malware analysis report

Static analysis result for SHA-256 77af86fa8cb7a604…

MALICIOUS

PDF

76.1 KB Created: 2021-09-18 10:26:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6834101426fe8a53a72212bfe68ba4b1 SHA-1: f37a33377acb433037f6040ad8310a7c1a22d37f SHA-256: 77af86fa8cb7a604040777eb849f9dfea02cfa517ef96a071a3d7ac55c868dac
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these links. The file's structure and the nature of the URLs suggest it's designed to lure users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.truck-transport.com/ckfinder/userfiles/files/37981441552.pdf In PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/73129059535.pdfIn PDF document text
    • http://bisenzia.it/userfiles/files/xibexotenuwu.pdfIn PDF document text
    • http://fipjp.com/userfiles/file/puxegesu.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/gimebomozulifuvewewoli.pdfIn PDF document text
    • http://firmen-bekleidung.at/userfiles/file/xivox.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16132de5e8fa0e---tekokixi.pdfIn PDF document text
    • http://gimhaejazz.com/fckeditor/userfiles/image/fiwibax.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/vudoxik.pdfIn PDF document text
    • https://copab.tn/216mag.svn/uploads/files/jivekewusokuxa.pdfIn PDF document text
    • https://vendax.ro/files/file/75687344761.pdfIn PDF document text
    • http://www.ctmmaximoravenna.com/ckfinder/userfiles/files/49353182327.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/hm0rruqumbhg0qdnqovoef3feu/bifas.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/161327e708ac93---16400789045.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/51373333192.pdfIn PDF document text
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/60264472597.pdfIn PDF document text
    • http://szzxwx.com/Upload/Upload/file/202191445243000.pdfIn PDF document text
    • http://idominjazz.com/fckeditor/userfiles/image/sanaduxowumijebixof.pdfIn PDF document text
    • http://moscowballet.ru/userfiles/file/16919520224.pdfIn PDF document text
    • http://beiks.info/public/file/97065554053.pdfIn PDF document text
    • http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/papopexi.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/99336478e32436c1d30ea9df158ea0c9/72063992141.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202109030212037469.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/6e23924355c5b48a8817dc6ccdfd17e5/82489900469.pdfIn PDF document text
    • http://purofirstli.com/userfiles/files/21673486245.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=farming+simulator+18+unlimited+moneyPDF 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_off0000c736.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC736 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000df48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF48 16308 bytes
SHA-256: 401aaf67f9a1de3286fb656b7299c4ff958b134a6740b8557ea57064394e87f3
font_02_sfnt_off00010957.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10957 11040 bytes
SHA-256: 54c8ce4ef5c98fe48a2f7b26ae1ffb3080b126e10396d1f69617830592d0723d