Malicious PDF — malware analysis report

Static analysis result for SHA-256 c421ae70522f0467…

MALICIOUS

PDF

93.8 KB Created: 2021-09-20 09:58:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c85caddfdd3e16044542006e523be35f SHA-1: 7154a75d3dc8b1ab3db3d0c945727838fa2044d3 SHA-256: c421ae70522f04674167e1a277cc7f5bf0f3029b1f19ff09d91fb80a4c490a3d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected by multiple heuristics and an ML classifier as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious sites. The presence of these links indicates an attempt to lure users to external resources, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://chcial.ru/uplcv?utm_term=auto+instagram+followers+free+online PDF link annotation
    • http://stilistspb.online/public/files/uploads/files/97636390166.pdfIn PDF document text
    • https://booburger.myagenda.cz/pictures/editor/files/1919182221.pdfIn PDF document text
    • https://promobryansk.ru/userfiles/files/zakapofamosawelefapi.pdfIn PDF document text
    • http://glassick.com/userfiles/file/jefafebewomexozazulopejaf.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614358fc0e4c7---xagokurutakufa.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16137116cdcfff---78132325873.pdfIn PDF document text
    • http://giustizianuova.it/userfiles/file/falerugufefatusiliwela.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/ec42d09da904d7ba611262a552582527/punixedetabivefodefoj.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/dfc9bcb8a87afc67a4db44fe2ec66189/93754983075.pdfIn PDF document text
    • http://aaykpn.com/uploads/editor/files/97035926842.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/pukufamaxasej.pdfIn PDF document text
    • https://laatuwhuisweerstralen.nl/upload/file/11178201075.pdfIn PDF document text
    • http://studiotravenzolo.it/userfiles/files/92613016534.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613384b24e582---giresora.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/06be99f3bb7dfc041e9cac3293fc1673/tovavanegu.pdfIn PDF document text
    • http://personnelstrategies.net/userfiles/file/13745782014.pdfIn PDF document text
    • http://elazentrale.de/images/uploaded/file/17964789082.pdfIn PDF document text
    • http://abwrosedale.com/uploads/files/93390627139.pdfIn PDF document text
    • https://questyme.ca/userfiles/file/28541670623.pdfIn PDF document text
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/mugiwenuxobija.pdfIn PDF document text
    • http://abimobiliare.pl/pliki/File/bajapisisa.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_off000108f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12108 10724 bytes
SHA-256: b3095c8492edb5224e55456e9cf9b3ca5596873519f7a611fec256d91fe4fad5
font_02_sfnt_off000139c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139C8 18416 bytes
SHA-256: 06155e9e29f5a55d97f34519d2eb19390e6a65905c10c97dbc12fc47cf76a574