Malicious PDF — malware analysis report

Static analysis result for SHA-256 2371933a0112494b…

MALICIOUS

PDF

82.9 KB Created: 2021-05-30 13:50:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 6a748c5701f077e549b1485c44b184d4 SHA-1: 2f455a6579e8bb6bb8219877092dfa6899a7b7a5 SHA-256: 2371933a0112494bcfde4e3000d6690f0e328325c2abc388bef7f35a7177a2f1
156 Risk Score

Malware Insights

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

The PDF file contains a link farm heuristic, indicating it's designed to host numerous external links, likely for SEO manipulation or phishing. The primary malicious URL identified is "https://bologen.ru/strik?utm_term=ejercicios+de+normalidad+resueltos+paso+a+paso", which is presented as educational material. Although no scripts were explicitly extracted, the PDF structure and the presence of external links suggest an attempt to redirect users to malicious content, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://bologen.ru/strik?utm_term=ejercicios+de+normalidad+resueltos+paso+a+paso PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4420248/normal_600dfeb059f49.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465687/normal_5feb534d59ec7.pdfIn PDF document text
    • https://josudirojupa.weebly.com/uploads/1/3/4/7/134729494/kofere-jivamil-pekapixubixam-kilovafomu.pdfIn PDF document text
    • https://furadigiwib.weebly.com/uploads/1/3/1/4/131407367/juxafiji.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/f60d83f2-589a-4816-a917-e307e58c847f/15134870601.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dab59c5e-3d8e-49b4-8c60-bc3d5da24d81/8564266254.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1fa42733-2d1b-4d6d-9107-894dff118876/bupukev.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/319e50ca-53ae-43f9-b50b-d712a02a7e2d/84014470877.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/545bbb87-2210-4dc9-b17f-b4f25835cdbb/pazebat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f54e89a2-f013-44d9-bc3f-11c05379ddac/74195669084.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9a7882fd-f5cd-4a00-bc0a-20097e448216/40432723406.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b84f2948-cd09-47c1-b57f-20f548447732/grimaldi_rp_discrete_and_combinatorial_mathematics_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/672fbc6e-a883-41dc-96b5-b08976bc0f40/griffiths_intro_to_quantum_mechanics_3rd_edition_solutions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2d1f2937-6a9b-4af6-9405-75a1572f2f80/20146890977.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/260de162-9b07-4a6f-9b7d-3237aa6400af/zombie_derby_2_mod_apk_unlimited_fuel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2521e34e-0407-4e0c-ae5e-2b691549c3c7/tojuv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b9786f4-e5d8-4259-ace3-cce74bbf7a01/16551100904.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fca9a6f8-4613-4c8a-a2d2-5d50245d2246/92221253583.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/29913b07-8db7-49ad-a579-0cb800941009/who_are_the_main_characters_in_the_breadwinner.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5748e5e3-cac7-4248-a83d-99ec8d564638/2007_harley_davidson_softail_custom_service_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/70d7a3a8-f98e-478c-aee1-828c665832d7/rinnai_gas_heater_japan_price_in_pakistan.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_off0000f582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF582 5136 bytes
SHA-256: fffe8085f1651edf3ae34f2a26c52c86958cb362cf6493277ac73cb9a9310097
font_01_sfnt_off000106d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D6 12480 bytes
SHA-256: 8e930639fd73552072615080b6e6a7441d0ca5823f8d2f17a2141aa28a34d247
font_02_sfnt_off00012fdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FDF 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f