Malicious PDF — malware analysis report

Static analysis result for SHA-256 11c3903ff6230d6b…

MALICIOUS

PDF

83.3 KB Created: 2021-03-15 17:56:35 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 95a03cba8417aa266dc393bfa88676a1 SHA-1: 2e56b2f280277e70d78f21762c30e7c620c3a68e SHA-256: 11c3903ff6230d6b2964e366a299881c03e5af508b24885d3ae4d0ccedb30b43
184 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and routes users through malicious redirector infrastructure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 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 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://yafferge.ru/strik?utm_term=flow+chart+template+microsoft+word In PDF document text
    • http://servisvds.ru/confession_of_a_shopaholic_book_seriespqaqp.pdfIn PDF document text
    • https://cdn.sqhk.co/fapetemiji/GhbaZcD/17432661827.pdfIn PDF document text
    • https://cdn.sqhk.co/nuvaratuji/m0IVgxD/34648539622.pdfIn PDF document text
    • http://retys.fun/78648107018io3i9.pdfIn PDF document text
    • https://cdn.sqhk.co/pugirunosamo/aHp7jdo/3897506002.pdfIn PDF document text
    • https://cdn.sqhk.co/xajezijanu/p4hil5W/veraboxaj.pdfIn PDF document text
    • http://spiritstudio.ru/28748651390s8ueb.pdfIn PDF document text
    • http://salea.site/excel_vba_find_string_in_rowbj31d.pdfIn PDF document text
    • http://groby-ritual.online/will_there_be_another_captain_underpants_booki00jo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367951/normal_5fda552a96795.pdfIn PDF document text
    • http://adminhalil.com/nelowoxexevex6o99m.pdfIn PDF document text
    • https://cdn.sqhk.co/sumefixes/tgjjbij/galactic_attack_alien_shooter.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4388842/normal_5fe259f665065.pdfIn PDF document text
    • https://cdn.sqhk.co/xororofomed/CVjb5gc/50586122337.pdfIn PDF document text
    • http://sayseedokg.com/which_rehearsal_is_routinely_performed_by_a_subordinate_leaderrj6rx.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366050/normal_6037da8604590.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/7ccbbf59-391f-48cb-a411-11c5a487dc01/which_is_cheaper_to_run_a_fan_heater_or_oil_filled_radiator.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4252f73e-6e74-4194-9869-af75796218f5/which_book_is_best_for_physiology.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/21ef345f-e04a-4cbb-b6a7-0e0d839cef23/georgia_drivers_license_renewal_requirements.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2e94742-e230-49f9-be7f-0d7bec39ef06/mrs_funnybones_book_by_twinkle_khanna.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dffcdf60-9d66-4443-826c-92ed23c1144e/71143383735.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fc73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC73 5124 bytes
SHA-256: 5a9c58c2d8cedbe0e9a05fd1925c8d61fdd4a916c2474c35daaccce56748efe2
font_01_sfnt_off00010def.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DEF 10308 bytes
SHA-256: 96e14203725375d6c0664f94d6a7e82586bbde0592281695b52d6017d3cce00d
font_02_sfnt_off0001314f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1314F 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c