Malicious PDF — malware analysis report

Static analysis result for SHA-256 75689c39335385e3…

MALICIOUS

PDF

68.7 KB Created: 2021-03-26 18:50:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 472b0c28181d1f54095151b464a41d32 SHA-1: 4c1e4bb9a66d82818d82c87f63adfaf18837f3f7 SHA-256: 75689c39335385e32322c67da3ab79de152589cd60a53345179a20a17e66f53d
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains a large number of embedded links pointing to external PDF files, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. Several heuristics flag the document as malicious, including a critical finding for linking to known malicious redirector infrastructure. The ML classifier also strongly flagged this PDF as malicious, and ClamAV detected it as a phishing trojan.

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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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.
  • 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://crophysi.ru/award?keyword=ihk+berichtsheft+pdf+nrw In PDF document text
    • https://cdn.sqhk.co/tatogevi/aE6MihJ/sinevexowonijigavofod.pdfIn PDF document text
    • https://vunukufe.weebly.com/uploads/1/3/4/6/134640969/kobigiwowanulomam.pdfIn PDF document text
    • https://wuvonavozaf.weebly.com/uploads/1/3/2/6/132695620/zerum_sokig_xijusubobe.pdfIn PDF document text
    • https://xuvarilanagore.weebly.com/uploads/1/3/4/4/134470983/nawinet.pdfIn PDF document text
    • http://wwwbcpzonasegura-viabcp.com/how_much_does_it_cost_to_mail_international_letterhivzp.pdfIn PDF document text
    • https://cdn.sqhk.co/bemovunilupo/gcf2Th3/oddmar_android_controller_support.pdfIn PDF document text
    • http://devlp.club/how_to_clean_an_lg_inverter_direct_drive_washerftvom.pdfIn PDF document text
    • https://jumomemokipus.weebly.com/uploads/1/3/0/8/130874307/nepebavapug.pdfIn PDF document text
    • https://cdn.sqhk.co/zivupowixede/gdfhjsr/adventure_landing_haunt_nights_2020_tickets.pdfIn PDF document text
    • https://cdn.sqhk.co/sanevujaguda/jSHjj7p/nabisomavimig.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/87fded3f-2a72-423f-a21c-cfc6bfddc9aa/pathfinder_ultimate_race_guide.pdfIn PDF document text
    • https://f1ddcea9-c323-452c-a4d3-aaefec61e50a.filesusr.com/ugd/defd8a_a54513b2a82544a0b66336c713a8f63b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c0edc08f-3eda-4525-a660-4af2f986c948/95865780636.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1abf5458-d87c-4671-8eda-b9d0f8ec4976/92049548760.pdfIn PDF document text
    • https://9534cc33-30dc-483d-bed2-8d5691710d48.filesusr.com/ugd/3835dd_c1a87e1bbfeb4394ad02e28bbe7224ad.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/fa679d4d-bfdb-4d0e-8d01-ad757ca88eae/porter_cable_router_1001-t2_parts.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD4B 5236 bytes
SHA-256: d6f8384e3f0522af8a15c0ae8adbc41115536518b865d4698c56beeda3f96a89
font_01_sfnt_off0000df25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF25 11268 bytes
SHA-256: f38605921b785ed4de41cb61066dd847b47c4b80f083486f14d18af1d60ff6b8