Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3688021d9cf0894…

MALICIOUS

PDF

73.6 KB Created: 2021-04-14 00:19:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: e86e9619ffaea2f37851d17589564263 SHA-1: 562a78b6fb75cc6fe5c1169d166e39ecc839262e SHA-256: a3688021d9cf0894779f5d477faf12698926df172b545a0bdeb7afecbf0facd2
186 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, containing a significant number of external URIs pointing to potentially malicious domains. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. While no scripts were extracted, the structure and numerous links suggest an attempt to lure users to external sites, likely for phishing or to download further payloads.

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://vilenefex.ru/strik?utm_term=the+great+american+songbook+foundation PDF link annotation
    • http://forexgeeks.net/cecil_textbook_of_medicine_26th_editionpo4n2.pdfIn PDF document text
    • http://avit0.pro/47831344583tn3eq.pdfIn PDF document text
    • http://mebelintera.ru/1kz435.pdfIn PDF document text
    • http://tdsevsvet.ru/how_to_ignore_a_guy_who_ignores_youp8n8o.pdfIn PDF document text
    • http://nopopoxozexa.iblogger.org/the_facts_in_the_case_of_m._valdemar.pdfIn PDF document text
    • http://wamepiguvoj.iblogger.org/visulepodekotaxa.pdfIn PDF document text
    • http://trastenmyqort.online/22564669057dotdz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8f1c0ae7-1ba6-4c51-a623-4d29f5e3aebb.filesusr.com/ugd/c1615c_e0695533cdd943ec85e4bd723f0e0e9a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/204547ec-2273-40f4-8007-1fc5ccb1eb51/sims_3_pets_xbox_360_cheats_money.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc643c3e-f64e-4d68-bb8f-e8416c6b306e/is300_6_speed_transmission_swap.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0cf7ef66-cd17-4999-bea7-57a6e2ecd43a/guwexixewodipedurapebuzes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b2a3876-7ea5-485f-adaa-62463e812154/3738216578.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/34c25b3d-3cc3-4922-96a6-bb0a62f5d028/wuxaniwujuzufifov.pdfIn PDF document text
    • http://tevomare.rf.gd/986602529.pdfIn PDF document text
    • http://fiderifi.rf.gd/74981602918.pdfIn PDF document text
    • https://b564fea6-732e-489f-a029-a72dc6590de2.filesusr.com/ugd/6a4619_796758e8b3dc4452bfa02eb226c47618.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ae07369-88be-42e1-aad3-dc3e09e62fe3/how_to_root_kindle_fire_without_computer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0746685-8f8f-41a9-a177-2f3c1db0d101/tales_from_the_shadowhunter_academy_audiobook_free_online.pdfIn PDF document text
    • https://8ee4d174-735f-4cd7-9396-c3a65dbcc337.filesusr.com/ugd/5ac313_1333d5c90d79438882d95e3df757c32b.pdf?index=trueIn PDF document text
    • https://c064424b-11a8-4e39-a524-24a74bcd733d.filesusr.com/ugd/54e393_ea453767dfcc482abc9ec9cd555d274b.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e094.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE094 5556 bytes
SHA-256: 27bdbeaebdda4d1be8fc119be5f1e54a0d553736e887d011282592473c64c539
font_01_sfnt_off0000f34f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF34F 11124 bytes
SHA-256: 5fe14cfd845e136444db30a6f27bcc886679145e07a762fc56c669bea888730b