Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c9d724bb49f0089…

MALICIOUS

PDF

78.3 KB Created: 2021-06-09 02:36:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 145d523df79a8cbaef36ca3fe8655ce9 SHA-1: 36b30a6d5093577db9c04357c84d2394af897de3 SHA-256: 4c9d724bb49f008928495eca00bdab993b4fa623fa9119a5e6f5dd55df8611c2
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with attempts to redirect users to malicious sites, potentially for credential harvesting or further malware delivery.

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://coretry.ru/uplcv?utm_term=polynomials+review+worksheet+answers PDF link annotation
    • http://vasvaripalmuzeum.hu/upload/file/27627460724.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b2553a78d---52495174909.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/c174d17fb419755bd24de62d424af9f9/zikesilomomozemirukolud.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/cdcf424b4209c9b4b49ecc6ef4c97a4b/95445078644.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/e049280ac8f52b4ee648b754ccc2be91/zajizibonab.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/28849268726.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160983cb2e9f75---37573298656.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc9bb58c67---38792556774.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/zenixetivakezarinojag.pdfIn PDF document text
    • http://healthywithhart.com/res/file/37582979804.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/5587bad307b1d26fcda5deda3402b606/63135964019.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file/%5C/6742572731.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160918b4a41d42---88113942046.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f8b47ce58f---4645062533.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
    • 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_off0000df48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF48 5244 bytes
SHA-256: c574f4bbb4818ae9971d8dd6bdd13ff8da912e3c72285c668cf9762dba13ee72
font_01_sfnt_off0000f102.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF102 11124 bytes
SHA-256: 523deb1baad1f5856a06220b9c8cd830bc01992e26fbace817b69e3ff94eb2e1
font_02_sfnt_off00011729.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11729 16092 bytes
SHA-256: e9fe716c2abc985b12a899a49d5539e4e8be1b56d50c083b30290d85a2a7c848