Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4682eb4e18346b3…

MALICIOUS

PDF

125.8 KB Created: 2021-04-09 17:07:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a928775c4354d39e5fb07ffa3b01f8af SHA-1: 869117171680caed0ff963b56bd87dbe4b387811 SHA-256: f4682eb4e18346b31acd73eb5199e6bff28d1e926686662f0d7553cf482fbe05
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 6

  • 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.
  • 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 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://vilenefex.ru/strik?utm_term=air+force+1+pixel+color+desert+sand+goat
    • https://kudaxemukuwofi.weebly.com/uploads/1/3/4/6/134691428/gamiwuzubazixej-temijenaf-xuzegemivusenuv.pdf
    • https://cdn.sqhk.co/wotinobeb/jScESie/mtx_gp_apk_download.pdf
    • https://dakaxepipuzegi.weebly.com/uploads/1/3/4/8/134869431/da4ea8e92.pdf
    • https://cdn.sqhk.co/bulelovuroga/9qb8idL/current_space_missions_to_mars.pdf
    • https://cdn.sqhk.co/legusovej/VWhghgN/87122414708.pdf
    • https://wexarasi.weebly.com/uploads/1/3/4/3/134351888/luvevowa_nurolenifukar_denuwatimorov_pezofis.pdf
    • https://jatilesaza.weebly.com/uploads/1/3/4/3/134316516/visojipe.pdf
    • http://vevaxogejaz.scienceontheweb.net/4454314742.pdf
    • http://tijudozi.scienceontheweb.net/why_does_my_cordless_phone_not_work.pdf
    • https://cdn.sqhk.co/womafafowix/6JCsjaO/benzodiacepinas_2017.pdf
    • https://fakokawiloduku.weebly.com/uploads/1/3/0/7/130775735/8200297.pdf
    • http://pasipodo.mypressonline.com/sound_insulation_materials.pdf
    • https://zipezeroluxufa.weebly.com/uploads/1/3/4/9/134904793/afbb4b08.pdf
    • https://cdn.sqhk.co/sawibevas/zijOyic/bikokubolole.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://uploads.strikinglycdn.com/files/f93c2d96-442f-42f2-ac44-a078b9e02656/welezafilewogisuzat.pdf
    • https://b01cffea-7a05-49e8-9781-04202a21c04b.filesusr.com/ugd/d5d855_52eb858942c34eab8c120c4973c903f3.pdf?index=true
    • https://uploads.strikinglycdn.com/files/19e6ec43-4df6-46ab-9b36-dbe678fb8114/23988258660.pdf
    • http://zobuwijezad.onlinewebshop.net/19091270917.pdf
    • http://jikelaxapexa.onlinewebshop.net/temixakavezoxolivaponam.pdf
    • https://ddb281da-11d2-423e-b83a-408ecf1f607f.filesusr.com/ugd/9db61c_ae5a301b104d4239ac04709af57a654a.pdf?index=true
    • https://20128683-61eb-4207-b985-d468b1a81fea.filesusr.com/ugd/0049ca_3ab2025174c849e7aae7685e9a368108.pdf?index=true
    • https://95a57b4d-a24c-4412-bd87-88f4f885d252.filesusr.com/ugd/011e4b_0e8810805742413a8d05c041b5367cb6.pdf?index=true
    • https://uploads.strikinglycdn.com/files/b0d1cf62-2b86-4116-93d6-cc3fde878e1c/50046683904.pdf
    • https://uploads.strikinglycdn.com/files/2a232169-e9c5-4de0-89d4-be23c9e4b7c0/what_is_the_standard_size_of_a_football_field.pdf
    • https://uploads.strikinglycdn.com/files/063cdbe3-1ec5-48dc-bc28-30601928a76d/dobubeviliwe.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001a21a.bin
924fe94094d74e9688e1b8db66f1a29ff4f8efa328928eb4e1aa88e363b2045f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A21A 5220 bytes
font_01_sfnt_off0001b3ea.bin
da8b92a96ee1f0f09b5315112a2df8c10ac1b87e4f0efbb2dbefa0fe47019d50
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B3EA 11272 bytes
font_02_sfnt_off0001da4f.bin
cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34
pdf-font-stream PDF embedded font (sfnt) at offset 0x1DA4F 4324 bytes