Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc34eb369e7fb7c4…

MALICIOUS

PDF

77.6 KB Created: 2021-03-25 02:42:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5bfba7a83710ef2e3c6624dd4773b7b0 SHA-1: 78ac3cade15222421f4c37511df41e49d7aeb807 SHA-256: fc34eb369e7fb7c471f94ea0b90061c8a984ff43e57a485e005cdbb3ae3840ef
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the presence of a link farm with numerous external URLs, many hosted on disposable domains, suggesting a phishing or SEO manipulation scheme. The embedded URLs and the nature of the heuristics point towards an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://soxebez.ru/123?utm_term=html+to+pdf+c+stackoverflow
    • https://cdn-cms.f-static.net/uploads/4444110/normal_5fda6396aa2d1.pdf
    • https://cdn.sqhk.co/radofufalam/Lhbjfgd/lucky_draw_cod_mobile_prices_philippines.pdf
    • https://guravigipide.weebly.com/uploads/1/3/2/8/132815190/5924004.pdf
    • https://lozezuxugi.weebly.com/uploads/1/3/4/0/134016676/2dfd32474c6c.pdf
    • http://lightsex.ru/loralowinogubujejakouzzpc.pdf
    • https://cdn.sqhk.co/rukokota/bij9QJn/periodic_table_in_gujarati.pdf
    • https://static.s123-cdn-static.com/uploads/4387808/normal_5ff7f221a038a.pdf
    • http://confirmyourverifiedbadge.com/inlet_outlet_surf_reportaydmk.pdf
    • https://cdn.sqhk.co/sewizefaxiki/faKihHO/51195959207.pdf
    • https://patawera.weebly.com/uploads/1/3/4/1/134131312/2315966.pdf
    • https://kowezuvive.weebly.com/uploads/1/3/4/6/134603832/kezakekanis.pdf
    • https://cdn-cms.f-static.net/uploads/4443594/normal_602f309993a26.pdf
    • https://vugevosuza.weebly.com/uploads/1/3/5/3/135328642/tozobirel.pdf
    • https://rexajubimazon.weebly.com/uploads/1/3/4/8/134884463/5129315.pdf
    • https://jagunafine.weebly.com/uploads/1/3/4/3/134363358/613e2.pdf
    • https://raxorevowipafe.weebly.com/uploads/1/3/4/7/134765671/fabifibanaxenub.pdf
    • http://tpdreport.com/65612118391gvuxz.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://67dbe094-6b68-4a2c-870f-9bd980043d88.filesusr.com/ugd/cff74a_02b6d13003cf4a6d90f5ba46c870f7d3.pdf?index=true
    • https://dd7ee03d-3646-4e01-a1e1-4c0a7e2c9e57.filesusr.com/ugd/d7ba0f_8aa00763c4d649709d3612119600e330.pdf?index=true
    • https://e028ba52-6c86-493e-86b7-fecf7cd1c3eb.filesusr.com/ugd/bcb9fd_0db32ecf543c4b19bc104bf29ece70b4.pdf?index=true
    • https://4121a797-204a-431c-92a8-8e24072fb342.filesusr.com/ugd/b972d5_f77af78cf7184141a0aaea2bd0070375.pdf?index=true
    • https://e1d5fa5a-667c-4d22-bb72-2ec96b4ed0f7.filesusr.com/ugd/01f30d_f0bcc4cbc6e74bfd92c113d979075a3e.pdf?index=true
    • 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_off0000e10e.bin
99e036bcf468b1459731ac6eded753a685907d785d68fad5cc685c6bd0d0913e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE10E 5112 bytes
font_01_sfnt_off0000f28d.bin
d47d142ad77355eccd95bccab047982ff62b9d194985872001baec13c478fde8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF28D 11840 bytes
font_02_sfnt_off00011b18.bin
1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B18 4324 bytes