Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a990c6b02775900…

MALICIOUS

PDF

81.5 KB Created: 2021-04-07 06:13:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: ba5dca6d5506d2c92ede23a7c9f2d5c2 SHA-1: 8051ccb7130b079500b685a5c354ad8a80d3f5c1 SHA-256: 5a990c6b0277590052ec5d1345eedb3ae63f98042b0f34707ba0fb226d26dced
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to disposable domains and are likely part of a link farm designed to manipulate search engine results or redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically phishing or trojan delivery. No scripts were extracted, but the PDF structure itself facilitates the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=safety+1st+dino+walker+manual In PDF document text
    • https://cdn.sqhk.co/simunenij/hpjeii0/big_launcher_alternative.pdfIn PDF document text
    • http://mp4.design/4686464147un4iy.pdfIn PDF document text
    • https://cdn.sqhk.co/lexuxeza/ic02gis/administration_dfinition.pdfIn PDF document text
    • https://cdn.sqhk.co/tifomogoketu/igiczij/sivajojirizupojotolugavo.pdfIn PDF document text
    • https://cdn.sqhk.co/mugejufunij/ckwCgg9/guitar_hero_warriors_of_rock_band_bundle_wii.pdfIn PDF document text
    • https://cdn.sqhk.co/xedasuzefer/icaghmV/26570225080.pdfIn PDF document text
    • https://cdn.sqhk.co/fegukajebaj/ieijhO4/borezi.pdfIn PDF document text
    • https://cdn.sqhk.co/mosugukasiba/jfhgSjg/durokututemenokapebup.pdfIn PDF document text
    • http://sandiego-podcasts.com/listening_worksheets_with_audio_for_kindergartenfphj6.pdfIn PDF document text
    • http://legalvictory.group/44242082596146fz.pdfIn PDF document text
    • https://cdn.sqhk.co/lejesapazud/geURDBp/savings_tracker_app_android.pdfIn PDF document text
    • https://cdn.sqhk.co/bogovureg/ggigihG/sniper_rifles_cod_ww2.pdfIn PDF document text
    • https://cdn.sqhk.co/bitowiso/SieD3dA/95000706083.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
    • http://pimibini.epizy.com/centerpoint_energy_power_outage_reporting.pdfIn PDF document text
    • https://cb2d4818-2134-4ea5-ae57-1bc45cfc4292.filesusr.com/ugd/7e787c_fb7ef8db599c409da48268af5c417efc.pdf?index=trueIn PDF document text
    • https://03df18d0-0a94-4077-8b44-1f3cf8b7c870.filesusr.com/ugd/23a6c3_6a1b7c8b4dae404394beb12f0ea116ce.pdf?index=trueIn PDF document text
    • http://vaxomuterok.epizy.com/80886945840.pdfIn PDF document text
    • http://jejafajiw.rf.gd/count_character_in_excel_sheet.pdfIn PDF document text
    • http://xelidamos.epizy.com/rural_mailbox_installation_guidelines.pdfIn PDF document text
    • http://gatokelemek.rf.gd/64619105909.pdfIn PDF document text
    • https://ff4d9611-e7ea-45f2-85d3-f0b464ef817f.filesusr.com/ugd/48f461_96de71b96ac843abb05ab7b7f3c5ceb8.pdf?index=trueIn PDF document text
    • http://fipenalexaxa.epizy.com/xatunavozukiratuzi.pdfIn PDF document text
    • https://28ae28a3-27cc-4d38-be83-0de1f6925f83.filesusr.com/ugd/454016_a2676c2d6b19417b87b25819d58046c8.pdf?index=trueIn 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_off0000f4c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C4 5348 bytes
SHA-256: 4765961fa54b91206336c1cf677f5c407bcff810a0270fa2eefb055f322801f8
font_01_sfnt_off000106f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F4 12272 bytes
SHA-256: 49c41982c121c519a8e590277203391bd88f2350b97a1cb8fc0d2513efb4f304
font_02_sfnt_off00012fc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FC5 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361