Malicious PDF — malware analysis report

Static analysis result for SHA-256 f171e1c39bc6052e…

MALICIOUS

PDF

78.0 KB Created: 2021-04-04 06:04:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 542e39e81198d8cc7c51e425985af4c8 SHA-1: bd134f69cfca551b1d7abb2e12f6396e242d94b5 SHA-256: f171e1c39bc6052e35e79069181da6b61e9a59babd0170138e83d9933df6070b
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a significant number of external links, many hosted on disposable domains, suggesting a link farm or SEO manipulation tactic. One of the primary URLs, 'https://nipisod.ru/123?utm_term=anti+terrorism+shooter+game++for+android', appears to be a lure, while others point to a large collection of PDFs. No scripts were extracted, but the PDF structure and link farm behavior are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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 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://nipisod.ru/123?utm_term=anti+terrorism+shooter+game++for+android PDF link annotation
    • http://takovod.66ghz.com/92214695813.pdfIn PDF document text
    • https://wexotagupoma.weebly.com/uploads/1/3/2/8/132814474/tefipibetiloz.pdfIn PDF document text
    • https://vidimepimexuja.weebly.com/uploads/1/3/4/6/134626803/432217.pdfIn PDF document text
    • https://fuvetozexogix.weebly.com/uploads/1/3/0/8/130874326/kavijurovutuvut.pdfIn PDF document text
    • http://zisumabegol.22web.org/fake_blood_cancer_report_download.pdfIn PDF document text
    • https://gogabaxada.weebly.com/uploads/1/3/4/8/134852864/vanadujebi_dafimakoviruma_fiwefazoxej.pdfIn PDF document text
    • https://nopovufarake.weebly.com/uploads/1/3/1/3/131379277/jisufivajosijunegik.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493905/normal_6035ce7ace1d5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4373522/normal_600326804adab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486201/normal_604e38d652667.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484804/normal_5fe4db4d93257.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403820/normal_604889c5ed3a6.pdfIn PDF document text
    • http://xenemedoxasuv.22web.org/ketimibirazukawixilumi.pdfIn PDF document text
    • http://dogopanasukodum.22web.org/sessions_de_formation_traduction_en_anglais.pdfIn PDF document text
    • https://rudanivaxaf.weebly.com/uploads/1/3/4/4/134497940/tupawukirafiten.pdfIn PDF document text
    • https://kaxogirigajel.weebly.com/uploads/1/3/4/6/134611066/68c6d4.pdfIn PDF document text
    • https://ditaziretuviki.weebly.com/uploads/1/3/0/8/130874055/miwibuv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://batawovajupofu.rf.gd/gastropoda_mangrove.pdfIn PDF document text
    • http://dekuroveki.rf.gd/92533885217.pdfIn PDF document text
    • http://zawagebojirowe.rf.gd/loxepij.pdfIn PDF document text
    • http://putajisuguxavul.rf.gd/18589787395.pdfIn PDF document text
    • http://tenazapuxukov.epizy.com/gone_down_the_rabbit_hole_meaning.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_off0000f262.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF262 5280 bytes
SHA-256: b1939b113d0e0adac694534f6ff2c040d951561f6e73698091e6ae6de03fec98
font_01_sfnt_off0001042b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1042B 10648 bytes
SHA-256: f1db836d206177c5d2e977e128c70db7874646875140490073e96d06d70df2b1