Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f7a97d72f788a94…

MALICIOUS

PDF

75.1 KB Created: 2021-03-15 17:44:28 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: 3956ef6c981a16075c1ced4a4aec9209 SHA-1: 4f5617dbcc4d227f57efe01ccb0fd62f1f5ebede SHA-256: 8f7a97d72f788a942a3e59e228d32f73d4571b6dd8446175f6e7bce56c1c25dc
126 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to disposable hosting and are part of a link farm, suggesting a phishing or scam attempt. The primary URL, https://vilenefex.ru/strik, is likely the destination for the lure. No scripts were extracted, but the PDF structure and URL patterns are indicative of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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://vilenefex.ru/strik?utm_term=boy+scout+merit+badge+salesmanship PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4381543/normal_60302eccc28da.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418391/normal_5fceee36c4f3f.pdfIn PDF document text
    • http://dutarotanazosuv.medianewsonline.com/balatif.pdfIn PDF document text
    • http://kir.center/83911083473w1gdx.pdfIn PDF document text
    • https://cdn.sqhk.co/kutajanode/ha9hcXv/lethargy_definition_greek_mythology.pdfIn PDF document text
    • https://cdn.sqhk.co/pelopuxi/fFjfdij/27316820250.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420459/normal_6047ca89797cd.pdfIn PDF document text
    • http://erogan-columbia.site/apex_launcher_apkpurezye2z.pdfIn PDF document text
    • https://cdn.sqhk.co/tosuwukiwate/WjhDh9u/33696259825.pdfIn PDF document text
    • http://shoop-fn.ru/44237018298ws408.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483103/normal_5ff7b911b2c8b.pdfIn PDF document text
    • http://mipexalazalekab.getenjoyment.net/argumentative_essay_about_immigration.pdfIn PDF document text
    • http://falorilipeb.mywebcommunity.org/the_black_cat_vocabulary.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478683/normal_5fd6d77abde24.pdfIn PDF document text
    • https://cdn.sqhk.co/tijanukubo/cIBjfid/41269393043.pdfIn PDF document text
    • https://cdn.sqhk.co/letaziseb/qijQgjV/ghana_airtime_top_up_online.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4a39c6c9-989b-4d11-b2d8-cc0becc7f193.filesusr.com/ugd/ef0078_c58c2b25ef654709a6e128e01153877d.pdf?index=trueIn PDF document text
    • https://b6086c54-8ef4-40f3-ba18-bbbb993b339e.filesusr.com/ugd/36e927_519ea118ab8a49b7aeb78f95f8b5afa1.pdf?index=trueIn PDF document text
    • https://bac325b5-3710-4a60-ba01-c1ac5e8a7650.filesusr.com/ugd/c111de_74f8cca22d97492a8ff4c5ea392b4529.pdf?index=trueIn PDF document text
    • https://8c285b57-3156-47ce-881b-df665acc117b.filesusr.com/ugd/8d46c2_a780a0b5cd0449a5b08a90fe5cfae8ec.pdf?index=trueIn PDF document text
    • https://74269c25-1731-4359-90d4-804f54ef9c1c.filesusr.com/ugd/b5973a_0dd2fb4b41c94229ae9b3efacfa85365.pdf?index=trueIn PDF document text
    • https://c84d532c-3b33-47d6-96aa-4134a1164eb1.filesusr.com/ugd/6d45f6_216d2172c65543be8f6ff42bef3e1846.pdf?index=trueIn PDF document text
    • http://viniwowosur.onlinewebshop.net/27194843789.pdfIn PDF document text
    • https://dbb1fad9-9c05-458f-9e32-bc0b7f65d7ec.filesusr.com/ugd/451461_83def9c2f713400ca0900128d8c8537a.pdf?index=trueIn PDF document text
    • https://d4180a97-8dd0-4bf1-9e2f-d1b128d1a64d.filesusr.com/ugd/ae059d_35b5f2f7ad6c42a28d0491bedbfe96c9.pdf?index=trueIn 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_off0000e7f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7F0 5780 bytes
SHA-256: 61169b00674c429402cc9e6c1ab02fffed5eb7f1897e1b8ea931072844f4b6a2
font_01_sfnt_off0000fb79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB79 10260 bytes
SHA-256: db470c3145bd724c20964da0ea5e9896269d9c2b9dfd8f5f4e92ef3d53ef40f5