Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd1cffd5aa27eec4…

MALICIOUS

PDF

79.0 KB Created: 2021-03-31 10:39:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: a143ceb46ba1b2e8769c324af23bf753 SHA-1: 1bf2080b27639f66972208a105944942c937264f SHA-256: bd1cffd5aa27eec4c777f81ec42304dc0f6b3a298472f6152414bcb49d40f41d
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, indicating it functions as a link farm. Several heuristics, including PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM, confirm this behavior. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to direct users to phishing sites or to host further malicious content. The embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://soxebez.ru/wix?keyword=best+race+for+berserker+tera+pvp PDF link annotation
    • https://cdn.sqhk.co/detazido/heSyChc/zanow.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445882/normal_602607c5da07b.pdfIn PDF document text
    • https://cdn.sqhk.co/goworonol/phgkkKZ/99950484786.pdfIn PDF document text
    • https://cdn.sqhk.co/dakagugi/jf6Ejb7/avtosh_2_charx_android_oyun_club.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4503584/normal_6013af1d60da7.pdfIn PDF document text
    • http://dehydratedoriginalgoodness.com/jorge_luis_borges_y_sus_principales_obrasgglas.pdfIn PDF document text
    • https://cdn.sqhk.co/nalomuxe/gfVlkn7/sudejut.pdfIn PDF document text
    • http://ionatr.space/7432460474o6uq4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4390999/normal_5fe25ff25d1d5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4374839/normal_5fcf518ccf92c.pdfIn PDF document text
    • https://cdn.sqhk.co/bivotiboma/eljcjhL/fios_tv_app_for_windows_10.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493195/normal_5fd645f2a3c69.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://aabf49e0-5477-4fd2-8456-a986ef8f2a87.filesusr.com/ugd/9e14ca_095e0b2d70ce462481508ba3fbba037c.pdf?index=trueIn PDF document text
    • https://5efcf519-4c71-4be9-a00f-e1d47ba804c5.filesusr.com/ugd/ebcc4b_6d25bd17d68743d0b557c4382e247f12.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tuletivotarupu/beautiful_landing_page_templates_psd.pdfIn PDF document text
    • https://s3.amazonaws.com/zabevog/jsc_result_2018_marksheet_comilla_board.pdfIn PDF document text
    • https://s3.amazonaws.com/vibasujefir/16366365372.pdfIn PDF document text
    • https://e192e36c-395d-4660-9df6-aa7aed00c30a.filesusr.com/ugd/3aee12_4b1b5a49236845fc91a806fcea02ab3b.pdf?index=trueIn PDF document text
    • https://9e2b3e3a-6a02-4d3b-8ba9-5acc01041672.filesusr.com/ugd/66c878_e8367a0781fb4afb89f4430280e3bc89.pdf?index=trueIn PDF document text
    • https://0e627107-309b-4451-a84d-e7064c41fccd.filesusr.com/ugd/04c368_2681cd3134cb4e89902cddfadd6d03fa.pdf?index=trueIn PDF document text
    • https://bb55feb6-a0c4-48ae-8f72-aea2c45912f8.filesusr.com/ugd/b9801a_cacc07cbd0e345c28faa085b63762ba9.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fosagobomap/league_of_legends_post_game_chat_report.pdfIn PDF document text
    • https://a0d2adcf-75bd-42a9-a42a-c23e1c6e9e1a.filesusr.com/ugd/85c99c_3590f655f7974bffaeecd1fb4ab95299.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/ravuxudibure/12518253730.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7E9 5288 bytes
SHA-256: ba17cf399fa665c98dfb8af23e1c2cc98fa6a588bc82235271786c783376368a
font_01_sfnt_off00010a02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A02 10756 bytes
SHA-256: a7bb2eb865b704c9e985f4f7636690e560f0507e27902fc21ee2abdb9764c951