Malicious PDF — malware analysis report

Static analysis result for SHA-256 4151aa4f51cbe1a3…

MALICIOUS

PDF

71.8 KB Created: 2021-04-14 15:11:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 08f6dc39b059ea44ee36729eeb2b184e SHA-1: 54bcd96ee9876797bcf5938f89d6cd5748b81985 SHA-256: 4151aa4f51cbe1a31203c427f4063ee90491685256a1dceae57b0f59e48d2c6f
184 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical alert for linking to known malicious redirector infrastructure. The ML classifier also strongly indicated maliciousness. The embedded links, such as 'https://yafferge.ru/strik?utm_term=audio+libro+amar+o+depender+de+walter+riso', are designed to redirect users to potentially harmful sites. While no scripts were explicitly extracted, the PDF structure and link farm heuristic suggest an attempt to distribute malicious content or phish for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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=audio+libro+amar+o+depender+de+walter+riso In PDF document text
    • http://towesijep.iblogger.org/outlook_365_not_opening_attachments.pdfIn PDF document text
    • https://cdn.sqhk.co/tivinarafuvu/Kid2KB7/jotojukobewawizixomiwe.pdfIn PDF document text
    • http://zowomojagobipur.iblogger.org/30193115505.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477139/normal_6056e393c45ad.pdfIn PDF document text
    • https://cdn.sqhk.co/zonigita/Whahgha/sogovarisu.pdfIn PDF document text
    • http://jimurizo.22web.org/guidewire_claimcenter_data_dictionary.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378153/normal_60144dc4d473f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417997/normal_600c71876cfaa.pdfIn PDF document text
    • http://domivenujivo.22web.org/zozilobididogozugedaji.pdfIn PDF document text
    • https://cdn.sqhk.co/daribugubive/hdyjc7X/beat_hazard_ultra_apk_2018.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4389793/normal_5fff43d2032e1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://tofaveme.epizy.com/basic_arrhythmias_8th_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/50078797-617c-4b01-afb7-b14349086fce/fovaparuxek.pdfIn PDF document text
    • https://45ae50e1-98a8-4501-9ad6-fc0df438eb43.filesusr.com/ugd/b16523_68828c41631d401e805c3cfe191e2f00.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ae461db9-666d-4827-987b-594c3c1f378e/24413045407.pdfIn PDF document text
    • http://kinapemib.rf.gd/ccna_security_210-260.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dcf4fa10-34c8-4d12-83cf-077cbcac29e9/jbl_flip_5_bluetooth_speaker.pdfIn PDF document text
    • https://f27bca7f-571c-471d-9e77-92385e6dfcd0.filesusr.com/ugd/9a0fa1_4a0e80f0e0864cc9addfef7d8e6d6b53.pdf?index=trueIn PDF document text
    • http://zuwodiruvukima.epizy.com/why_prisms_are_used_in_binoculars.pdfIn PDF document text
    • https://e82ff0bd-cb1a-4782-8b92-0a0fb7657660.filesusr.com/ugd/d17951_561aa9bc2dd84f37a3a349522c1edd0f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/85d474b5-291a-4a2d-885e-8a9a4d17c8fa/33089179414.pdfIn PDF document text
    • http://serozefa.epizy.com/asset_lifecycle_management_process.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1bf4716-4203-4fac-8f56-3d50902ff7fb/56235770687.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_off0000d921.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD921 5324 bytes
SHA-256: 86cd55f7a96c929c833294a64db2f45205f039602eab3c5e95d1920bbf09210c
font_01_sfnt_off0000eb2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2B 11200 bytes
SHA-256: 994f67b828858c545cf891284089bfa8759d384d524489c6af3d94c0a40ba45c