Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9f4a277c982ea5a…

MALICIOUS

PDF

81.9 KB Created: 2021-06-10 20:53:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: fbb542505d0a10e4fd0f18df936d2b0b SHA-1: 15999e895437979dafb32929f93267dae9a33e0a SHA-256: c9f4a277c982ea5ab3009b18a07739726959b8b2e185544fe0aa14a0c23b7e97
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URLs point to a common tactic of using compromised sites to host or redirect to malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://medvor.ru/uplcv?utm_term=mature+black+mom+tube PDF link annotation
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a66164410aa---29825215421.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5cbdf1beb---49159408939.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160997edecd3e4---85914793609.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ec4322d05d---20980925488.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/b9e31ccce0ead7a8e9d2a7226ac6ea56/3193290348.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/tgt1bsaomole9h77tvondqv2jf/paninirewefimavisavexeb.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079840860dfe---zideguveserorutufagunerul.pdfIn PDF document text
    • http://strandedtattoo.net/file/6122023007.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/983bffdd3d1076a7a1e9bcf9ce0dcc5b/36026059068.pdfIn PDF document text
    • http://cnex.cc/images/blog//file/zozulutakerajitil.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/67b5985hnl1lt7n49cvj303dfp/wexewomuxavupiwaz.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/67ce3d6cd685f7fcb4c1a97dd131863b/lasikabixup.pdfIn PDF document text
    • https://www.kasekimi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080ce5fcc3e7---77305138869.pdfIn PDF document text
    • http://anandtouristcorporation.com/uploads/55764459998.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A82 4976 bytes
SHA-256: 68059d88d4644a39f1611553d5c5c7a152f0166eb25a9cf4da8fd92837d8d49c
font_01_sfnt_off00011b67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B67 9280 bytes
SHA-256: 64a005b1355bba74ac754e57b49d6fe604331c276b494b7f75f7b1528cd190cb