Malicious PDF — malware analysis report

Static analysis result for SHA-256 f58ddd7278684a21…

MALICIOUS

PDF

89.4 KB Created: 2021-06-14 10:39:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: ef82c44829e8fead2e517205316cddec SHA-1: 40e1553d5e7f2e51778c7b7488ccc10ef49ce537 SHA-256: f58ddd7278684a21708a67c05eff6991dc32890993e0438a21dc3d620856a14a
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm, with several pointing to potentially malicious or SEO-abusive content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these linked documents. The document body is heavily obfuscated and does not provide clear textual clues, but the overall structure and heuristic firings point to a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://coretry.ru/pbw?utm_term=all+cast+receiver+pc PDF link annotation
    • https://sanositew.weebly.com/uploads/1/3/1/8/131872303/4949680.pdfIn PDF document text
    • https://fasukawoj.weebly.com/uploads/1/3/1/4/131453618/a8fb37b295d6e.pdfIn PDF document text
    • https://gupoxebexu.weebly.com/uploads/1/3/4/3/134337811/29a28acd54abbf.pdfIn PDF document text
    • https://mamonujiduvef.weebly.com/uploads/1/3/4/5/134525279/mojixisij-rutexosapom.pdfIn PDF document text
    • https://vekibapovadivoz.weebly.com/uploads/1/3/0/8/130873848/1fdab37.pdfIn PDF document text
    • https://rowimunikak.weebly.com/uploads/1/3/5/3/135346477/6167621.pdfIn PDF document text
    • https://muroladenigi.weebly.com/uploads/1/3/4/8/134870938/fejetadovi-kepinalesiwipu-gajadebabep-rijavofupogifo.pdfIn PDF document text
    • https://tuvukorop.weebly.com/uploads/1/3/1/8/131857527/d2dfeffb837.pdfIn PDF document text
    • https://bukuduribo.weebly.com/uploads/1/3/1/4/131454389/7800995.pdfIn PDF document text
    • https://dexuzese.weebly.com/uploads/1/3/0/8/130813054/nupusix_zigiguv_nobamovosuxozub_nemeranotike.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/30637113-7c22-4cb1-8e47-0722391e8375/senabedod.pdfIn PDF document text
    • http://jorowad.pbworks.com/f/41273004420.pdfIn PDF document text
    • http://vajaxasave.pbworks.com/w/file/fetch/144452838/vebonomawazurigupasubu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f608fceb-e540-4cef-86b5-17c15f31dbcf/how_to_clean_a_ducane_furnace.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ec8cbcb1-e07d-44a5-9821-506685c59567/suvonugodemikib.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/87a8ef3f-bb46-45a5-9222-8b0e5dfe2acb/diary_of_a_wimpy_kid_the_meltdown_yumpu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/09b93911-5bcb-422c-938f-d450144ce6ae/48_laws_of_power_book_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c87add3-9846-463a-bbc0-1d3f12e0791f/skyrim_early_game_tips.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/da2eeca1-ea77-4090-ad7f-4f8c17c1ebd7/kefomedikuvisosuti.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/06f8a240-f90c-4620-bbab-9fa821272731/push_by_sapphire_true_story.pdfIn PDF document text
    • http://tufukamapaf.pbworks.com/f/nepaxomewotivugowa.pdfIn PDF document text
    • http://dumunivuniv.pbworks.com/w/file/fetch/145192323/grammar_test_with_answer_key.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb338a1f-42f5-4358-87ca-33144e09c8c8/zaguwojisuporow.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_off000123ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123BA 4976 bytes
SHA-256: 036255499c5147d9894f5e28cfe4efdcefc275ecd30e256f96537eb81840a65f
font_01_sfnt_off000134ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134BA 10428 bytes
SHA-256: 68be6a5db5bd8fc388bf3cfac42c01a02db2659806f88941adf4d3ecfd34d3ba