Malicious PDF — malware analysis report

Static analysis result for SHA-256 8818d91dbb6f742e…

MALICIOUS

PDF

78.3 KB Created: 2021-05-01 03:16:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 107643a3888bb84f11dc5f707a0affbd SHA-1: a74e0b769374061d8967b49597176493c8e5f81a SHA-256: 8818d91dbb6f742e2e5a65124e7677268d8e6a5f3c190b7655c8d130756aee5a
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified as a link farm, with many pointing to disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were extracted, the structure and URL patterns are consistent with a malicious document designed to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://xajibur.ru/strik?utm_term=%25C2%25BFcu%25C3%25A1les+son+los+3+principios+de+la+econom%25C3%25ADa+circular PDF link annotation
    • https://cdn.sqhk.co/kurafuso/Pjjiehj/du_transfer_application_deadline_stanford.pdfIn PDF document text
    • https://cdn.sqhk.co/pepigovagove/bT32jdE/non_formal_education_meaning_in_malayalam.pdfIn PDF document text
    • https://danivuzi.weebly.com/uploads/1/3/2/6/132681213/zuwuxitumijoj.pdfIn PDF document text
    • https://liritetujom.weebly.com/uploads/1/3/5/3/135310948/wogogul.pdfIn PDF document text
    • https://cdn.sqhk.co/talurelope/aiihfhd/zefujebokekatav.pdfIn PDF document text
    • https://mujiborabasovu.weebly.com/uploads/1/3/4/5/134590634/3534354.pdfIn PDF document text
    • http://luwimifamofuper.iblogger.org/fajibimana.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://memaded.epizy.com/25437955871.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ccedaa24-9ccd-4320-b0b0-ca97ddaf2e9a/minecraft_bedrock_survival_servers_1.16.20.pdfIn PDF document text
    • http://netikadikis.epizy.com/liruzenipebebeze.pdfIn PDF document text
    • http://dataluwemijelo.epizy.com/talaximepufudidemavuli.pdfIn PDF document text
    • https://ca30e0e0-ecf2-44ab-b6a2-fe26291458be.filesusr.com/ugd/34e21e_a27fdd67437041d5bc70783329a53364.pdf?index=trueIn PDF document text
    • http://doneresipudeb.epizy.com/is_there_a_dvi_to_hdmi_adapter.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e2c672f-7017-4528-8d83-7b39db8119a3/42024986477.pdfIn PDF document text
    • http://xuresubonadijif.epizy.com/butterball_electric_turkey_fryer_basket.pdfIn PDF document text
    • https://b5c4f4dd-ae1f-4f6a-908c-f463551224e4.filesusr.com/ugd/dafd60_beb9c7f8009e4e888a6f6d7aa7e32f52.pdf?index=trueIn PDF document text
    • http://novinijazop.epizy.com/xijopud.pdfIn PDF document text
    • https://ea7788ad-ef5a-48b5-911d-3ad522045378.filesusr.com/ugd/f3bfbb_b9d4e57bd7354f6e97ef08217b0a2672.pdf?index=trueIn PDF document text
    • https://8271b8e8-1520-4b18-8785-2fafc8cd33e6.filesusr.com/ugd/efc97f_f690f93d84ba4b4090c641bf2f90935f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f0cd3839-20ae-47db-bc59-ed0723e8a2a7/37750906551.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_off0000ee39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE39 5712 bytes
SHA-256: b24ca7c77da2b9802040cb2459ba82c84df08a67129b39580c07ebbb8048cad5
font_01_sfnt_off000100f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100F8 12148 bytes
SHA-256: 9d59f4e7277a541c3a8babca290f9cdadbeadce5f06b1ab04b6c0821c9bd5859