Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a6a987633d3f4d8…

MALICIOUS

PDF

95.5 KB Created: 2021-04-12 16:03:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 3d13cd878c50bf120eca2ac5135144d3 SHA-1: 549ce4eceb5aa71387425d8fb08c7ca7347fac2e SHA-256: 4a6a987633d3f4d8ec27fea0438a12ac5d0a4c2eec86b971e855dcd2fb2f4488
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://gimoguvi.ru/strik?utm_term=fifty+shades+freed+trailer+download+mp4 PDF link annotation
    • http://vuzetasavuxoso.mygamesonline.org/giwawuxa.pdfIn PDF document text
    • https://cdn.sqhk.co/xubipoxeguza/fByieij/free_slots_77777_games.pdfIn PDF document text
    • https://fevuvewuvadudu.weebly.com/uploads/1/3/4/6/134650824/3586dc62c6c207.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422909/normal_60427dcfb9470.pdfIn PDF document text
    • https://cdn.sqhk.co/tatidukigag/gGJhjuQ/download_game_steampunk_racing_3d_mod_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/lilajibusizu/7pijf6O/android_6._0_1_update.pdfIn PDF document text
    • http://bovewitavivebu.getenjoyment.net/mini_dachshund_puppies_for_sale_dallas_tx.pdfIn PDF document text
    • https://cdn.sqhk.co/wezufunin/gfgZjfk/startup_500_business_ideas.pdfIn PDF document text
    • http://wewofif.scienceontheweb.net/75903291063.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385647/normal_5fd7a5fa73f7e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372074/normal_601fe4502d18e.pdfIn PDF document text
    • https://wapojopaboxijok.weebly.com/uploads/1/3/4/7/134747084/domukotuv.pdfIn PDF document text
    • http://rosipale.scienceontheweb.net/xatuxu.pdfIn PDF document text
    • https://surevasod.weebly.com/uploads/1/3/1/8/131856145/568f6a7.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fixiwajavonuti.atwebpages.com/pirezedujukag.pdfIn PDF document text
    • http://seroritubofa.atwebpages.com/how_to_describe_sunset_in_a_poem.pdfIn 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_off00012913.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12913 3612 bytes
SHA-256: 1564562c5f5bb1865c5bd5b048e3c0254f571a237b6061e00372db912b95e77c
font_01_sfnt_off00013617.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13617 5520 bytes
SHA-256: 4ced4390b6a763a5f0cfdee3e4ccf3572056cf23dde56e00568a30615c94666f
font_02_sfnt_off000148d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148D8 11508 bytes
SHA-256: b06b10b94afd8580cc8ac5ea9ecf7f723ffd4b9a0a63ba3a55c459c31b2c849b