Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cdc164d0f95ef04…

MALICIOUS

PDF

73.6 KB Created: 2021-04-07 21:12:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: b71a46122647070db90dcc894562cc53 SHA-1: f693535fdd171ecf13b5a69a50622323e460730b SHA-256: 4cdc164d0f95ef04385aec82f98692115540717440e9153d63065147e6790d51
186 Risk Score

Malware Insights

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

This PDF document was identified as malicious by multiple heuristics and a machine learning classifier, with ClamAV detecting it as a phishing trojan. It functions as a link farm, containing numerous external URIs, with a primary focus on directing users to potentially malicious sites. The document's structure and the presence of many external links suggest an attempt to lure users to phishing pages or download further malware.

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://resalured.ru/wix?keyword=unit+of+inquiry+grade+3 PDF link annotation
    • https://cdn.sqhk.co/tezizejaropu/flaCjeF/sawomojorowizodanevova.pdfIn PDF document text
    • https://cdn.sqhk.co/susojareb/0ijDrwu/9415817271.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417827/normal_6020b4b907923.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367013/normal_605d76dd3fe4b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462708/normal_6023d31f3f065.pdfIn PDF document text
    • https://cdn.sqhk.co/gabironero/jcChf7M/97754469572.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378613/normal_602fa3ce33f51.pdfIn PDF document text
    • https://cdn.sqhk.co/zativojor/jeO3gfT/wbtw_tv_news.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451044/normal_5ff7c2161a985.pdfIn PDF document text
    • http://gegezuwe.iblogger.org/akbarnama_book.pdfIn PDF document text
    • https://cdn.sqhk.co/xubuzivo/eWEjcja/sipoc_analysis_template.pdfIn PDF document text
    • https://cdn.sqhk.co/fapewakuw/hQ6geNl/62811033160.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a4bd69a-faa2-495f-9359-c27fbc1036c4/fios_router_g3100_login.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f295b3f4-cd58-4b12-8c6c-dc32a02cfd6c/nelemos.pdfIn PDF document text
    • https://5c2cca0d-3a4e-48b0-93bf-8ac6c0c026cb.filesusr.com/ugd/271e65_8664b50a288a47f2ab4fff31b3bfcd46.pdf?index=trueIn PDF document text
    • https://3a7b682b-4b85-4b21-836a-a34929c8735b.filesusr.com/ugd/0cd3a8_5253a50ecc6f446a9e795a3616799730.pdf?index=trueIn PDF document text
    • http://kugibujupedo.rf.gd/apple_app_to_facebook_videos.pdfIn PDF document text
    • https://4ad55601-b8ab-4ae0-bc0e-e90069072326.filesusr.com/ugd/3aca14_7fd113b18e1d46d1809bc6f6c6c0930d.pdf?index=trueIn PDF document text
    • http://vubixegigag.rf.gd/89781576465.pdfIn PDF document text
    • http://sefobetibaboxi.epizy.com/kalizituxefofowav.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_off0000e307.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE307 5248 bytes
SHA-256: c8bdacebc704ea9c16d0f7b13bc2795e4b1fd7784d4e0fd27ab4aef3a56c16ff
font_01_sfnt_off0000f4fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4FC 10976 bytes
SHA-256: efc3af3df5bc0ca9692c9dd6c7cbd07936a8d60ff383dec499105e00c0b09556