Malicious PDF — malware analysis report

Static analysis result for SHA-256 41107136cd713b8d…

MALICIOUS

PDF

92.8 KB Created: 2021-05-18 17:44:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: b74d3050f934b4fd8e1247fa44f3f891 SHA-1: 56e1c5abe0bac32490ce8739735945b4a566b393 SHA-256: 41107136cd713b8db442a418d82b19939ac302c3a1f1914d92284ce9695260f2
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristics point towards techniques used to host malicious content or redirect to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • 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://jumiwimov.ru/strik?utm_term=sample+of+attendance+register+for+meetings PDF link annotation
    • https://jotuxopa.weebly.com/uploads/1/3/4/2/134265841/7983b747abb52.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377403/normal_5fd2605be6222.pdfIn PDF document text
    • https://lafajadisevo.weebly.com/uploads/1/3/1/4/131454770/65ec4fe99939fe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385028/normal_60697a079acd9.pdfIn PDF document text
    • https://nigukaxo.weebly.com/uploads/1/3/1/4/131453065/wirase.pdfIn PDF document text
    • https://doxiviju.weebly.com/uploads/1/3/2/3/132302912/jarafez_bezobubuvabur_lotol.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406229/normal_606a908748ed8.pdfIn PDF document text
    • https://semukozev.weebly.com/uploads/1/3/4/4/134493414/2102819.pdfIn PDF document text
    • https://sanijala.weebly.com/uploads/1/3/4/8/134889677/bevati.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454999/normal_5fe4ff9e50fb2.pdfIn PDF document text
    • https://woniwisupu.weebly.com/uploads/1/3/4/2/134266019/xofivadopeseri_zinef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403410/normal_6010d389ab5cb.pdfIn PDF document text
    • https://zeduxuvanoripi.weebly.com/uploads/1/3/0/7/130775880/bazadunu-nexiwi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452161/normal_60560a46d3581.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4502175/normal_606bcef8b1db5.pdfIn PDF document text
    • https://simiwulizolur.weebly.com/uploads/1/3/1/4/131455232/65ed1782fde1fb.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/aab40715-6f45-44b1-997a-a1589d4ba4c1/50157779731.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2080a66d-bcf5-4d4d-85d6-5c2124bd92d7/xiweron.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2e7a1a2-f1e5-469d-ae93-855198c6fdd4/pills_to_get_her_in_the_mood_in_nigeria.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ecb353f-4c4a-47c0-9746-346c64f064ae/learning_computer_basics.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000110a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A0 5580 bytes
SHA-256: c26a2db843dbcea664cdd4d667e0eefff10a75dad9880c29d0124de3355edbbb
font_01_sfnt_off0001237d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1237D 1596 bytes
SHA-256: e80d19f9f3f4c31a7d9518ca1a1cba1f35fe906d77e6bb57fb947f89c2d262bc
font_02_sfnt_off00012b9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B9F 10408 bytes
SHA-256: 25b97368ef0f9ad99a910e311b5a71f47cf74df1bc2e29decefe0cfedead0ae0
font_03_sfnt_off00014f74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F74 16144 bytes
SHA-256: f6e0f4a25f18a144688c6b7f40519a5efc98c72643b9054f89526e396d9b459d