Malicious PDF — malware analysis report

Static analysis result for SHA-256 623c6fae9a8ce9a8…

MALICIOUS

PDF

96.5 KB Created: 2021-05-08 19:10:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 625e50cca6e424768b5b4a78675498be SHA-1: f8d6ac0e17cc898a96eff87124047bdbe62a80dd SHA-256: 623c6fae9a8ce9a8ddffefb316b16c69015280f3080858f8c29054bbe512917f
186 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which are part of a link farm hosted on disposable domains. The heuristic 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a high volume of external links, with one suspicious URL being https://soxebez.ru/strik. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://soxebez.ru/strik?utm_term=america+is+a+constitutional+republic+not+a+democracy PDF link annotation
    • http://rmk4sale.xyz/historia_del_secuestro_en_mexicoj3k1y.pdfIn PDF document text
    • http://verification-help.com/tijurekuladorujoloravuppcgh.pdfIn PDF document text
    • http://grinallex.shop/70888795256xw9pi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://973697ad-ffa4-4f9d-85cd-0c9d1ea039ee.filesusr.com/ugd/5f5755_1b01cb9ce4214238878917abef11775a.pdf?index=trueIn PDF document text
    • https://ce2645ba-e89a-43d5-afff-5c0150757291.filesusr.com/ugd/c63dba_1840225bd35c49248abdcf9afb92dbc1.pdf?index=trueIn PDF document text
    • https://203e7bc3-08d7-4ecc-a8df-f797e0d4a079.filesusr.com/ugd/d4579c_6c136ce5d64b486abbf14b8297df9a64.pdf?index=trueIn PDF document text
    • https://8ed6bd9f-de2b-4923-b7df-82f95eb18a03.filesusr.com/ugd/7fa32f_64d4af6a9e39452a84946ebbc92d888f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0402014f-82d7-46cc-ab73-7f21c873412d/carlos_bulosan_america_is_in_the_heart_1946.pdfIn PDF document text
    • https://01d67eed-50ba-4ccb-8f82-c1581f7ed07e.filesusr.com/ugd/e3325f_dc2fbbc21ffe42cd8d354d03f78d0284.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/55f93bf8-b5f7-49d2-86e9-31dbad174e46/8640489562.pdfIn PDF document text
    • https://s3.amazonaws.com/palevijuj/vonala.pdfIn PDF document text
    • https://s3.amazonaws.com/bomifabipi/39180695620.pdfIn PDF document text
    • https://d12e84a0-9808-45da-82c6-613dfe540d1b.filesusr.com/ugd/dc8a8e_b6212935a91740cfb83939371223bb22.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6089b6f9-b329-48a0-b006-a8c68d4d0b56/manogededozunanivas.pdfIn PDF document text
    • https://s3.amazonaws.com/furunumaroxun/tuzolovurofuzudoruxe.pdfIn PDF document text
    • https://s3.amazonaws.com/limepusotanal/manual_reloj_casio_edifice_4334.pdfIn PDF document text
    • https://ba10d46a-d7c1-43af-8542-f1a50f31aa8a.filesusr.com/ugd/4dded2_5aa5763f977942239dfd9686b72716f2.pdf?index=trueIn PDF document text
    • https://f3dcd8e3-6656-4b47-a81e-a993d3c4f2a1.filesusr.com/ugd/aa9ef2_68db94efdb144d089f42fbf5cd4c5e12.pdf?index=trueIn PDF document text
    • https://52b03d57-94e3-497b-b2ee-5a576b8f136c.filesusr.com/ugd/67ae49_2cc13cf08b1b451db9d8ae595d04042c.pdf?index=trueIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012e63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E63 5332 bytes
SHA-256: f597b92e90d8cdcfaeb57e3f3f7cd25fd9287ecd12708aa9764abb2670512aa3
font_01_sfnt_off00014057.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14057 11072 bytes
SHA-256: c1405573520ebd122783797f59ca412f8acab06ef67fdc15e7e23665e3c826a8
font_02_sfnt_off00016641.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16641 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34