Malicious PDF — malware analysis report

Static analysis result for SHA-256 791fea4790954d20…

MALICIOUS

PDF

81.5 KB Created: 2021-01-18 16:45:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: e588c382a3504810e6779d699c47d0e4 SHA-1: 9cd8fd26ab96c531e3ffc12d9062acb86df84221 SHA-256: 791fea4790954d20eecde28d7bb0f095c7ca9dce678a1bb0bbb2afbd83016b83
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or SEO manipulation tactic. ClamAV detection and ML classification strongly suggest malicious intent, likely to redirect users to phishing sites or download further malware. The presence of numerous external URIs and a link farm heuristic confirms the document's primary function is to distribute links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://seumenha.ru/aws?utm_term=junior+android+developer+salary+in+dubai PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4463812/normal_5fb2ad34d20bc.pdfIn PDF document text
    • https://tulorikuxefuwi.weebly.com/uploads/1/3/4/7/134730127/2975754.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384472/normal_60035ed07f7d1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475382/normal_5fe9ac2f3a935.pdfIn PDF document text
    • https://zezefikopupom.weebly.com/uploads/1/3/4/6/134686460/84f3b14361.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468820/normal_5fa881b82dd82.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403410/normal_5f929f9469ae5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4456676/normal_5fdd3b63db9d8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476939/normal_5fbeb7f84fe43.pdfIn PDF document text
    • https://wemuxafav.weebly.com/uploads/1/3/4/8/134860001/naruganiw.pdfIn PDF document text
    • https://zewubonorow.weebly.com/uploads/1/3/1/3/131398185/6277688.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417319/normal_5fc5ba0f883d3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425211/normal_5f9c0830bd5c4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368954/normal_5fa7539701dc9.pdfIn PDF document text
    • https://vanewuzopawibo.weebly.com/uploads/1/3/0/8/130814706/jeposofemusom.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4479678/normal_5fcc476571887.pdfIn PDF document text
    • https://zadumeredevasax.weebly.com/uploads/1/3/1/4/131453870/gisetidekose.pdfIn PDF document text
    • http://tatajosak.22web.org/sql_server_date_timestamp_format.pdfIn PDF document text
    • https://nasoxatexiwek.weebly.com/uploads/1/3/0/7/130739087/nomosubobadami.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://bavajozobe.epizy.com/45313578059.pdfIn PDF document text
    • http://riramemixezu.epizy.com/campione_light_novel_volume_1.pdfIn PDF document text
    • http://mosasawimip.epizy.com/venenubosupesure.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_off0000f1ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AE 5044 bytes
SHA-256: 54668c9a8347e1a73c960ff033b7054c870562bf0007286a68df4614bfca24d4
font_01_sfnt_off000102d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D0 11440 bytes
SHA-256: 277d89915fbd3b4e927aef69da67326570e5373bb54cc4510dd7fad0a04d742c
font_02_sfnt_off000129b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129B6 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c