Malicious PDF — malware analysis report

Static analysis result for SHA-256 81129d15a346656b…

MALICIOUS

PDF

80.8 KB Created: 2021-06-09 09:08:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: db700e0db669352a9ea3f58d2a6e76d4 SHA-1: 57d7019b62c174128f6d416d860d0d61872f3864 SHA-256: 81129d15a346656bf62c3e2dc1410924c5954270803325dd343fad223b24d96e
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including ClamAV detection for phishing and a critical finding for a PDF link farm. The document contains numerous external links, many pointing to other PDF files hosted on disposable domains, suggesting an attempt to manipulate search engine results or distribute further malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://catamma.ru/pbw?utm_term=surah+manzil+mishary PDF link annotation
    • https://static.s123-cdn-static-d.com/uploads/4485826/normal_60b0a6b3b0d25.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4406482/normal_5ff98d74c3f02.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375088/normal_6025936694364.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417137/normal_602fc64c5d82d.pdfIn PDF document text
    • https://sazigusejif.weebly.com/uploads/1/3/4/7/134771803/f83c1d839e.pdfIn PDF document text
    • https://linusakeziri.weebly.com/uploads/1/3/4/7/134747074/45345ec.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418367/normal_5ff10f8b809f2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488817/normal_5feff1f338dd9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497685/normal_601ef587731d0.pdfIn PDF document text
    • https://pujapuvefebawu.weebly.com/uploads/1/3/4/5/134581836/958b824ed68d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420775/normal_604f54baa10d1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366375/normal_605bea0c0e61e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418783/normal_6055a229d4a35.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413016/normal_5fe070cd41953.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454822/normal_602983d7d30bb.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/dd419aa7-9a69-41b9-8230-676cbc9051f7/13452809131.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f3027246-e73d-4486-8e7c-e58e316714fb/bird_life_list_printable.pdfIn PDF document text
    • http://lumoxag.pbworks.com/f/cell_organelles_and_their_functions_matching_worksheet_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ef29a2ff-cbe0-4baf-9943-09b3a7b11d55/the_thran_mtg_book.pdfIn PDF document text
    • http://vimadutukad.pbworks.com/f/how_to_know_if_it_is_exothermic_or_endothermic.pdfIn PDF document text
    • http://gosirata.pbworks.com/f/soundtrack_boy_before_flowers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4fbbf129-6b6e-4992-a4ad-faa12c3013ac/aramco_approved_vendor_list.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e273.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE273 5180 bytes
SHA-256: c2e87f910fc32c360bf2d95361003ed15a2fa00b8670935806c607c78dc9688b
font_01_sfnt_off0000f3eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EB 12012 bytes
SHA-256: 5f91e82cd46f1b2450a32fe2144fd6eaa75c9ac197c2c2cc4aef0abd7e47c52a
font_02_sfnt_off00011bf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF8 17524 bytes
SHA-256: 60c099c07f2612e5171a432df8f4ae982c2c524acef622e52223dfc79c66098c