Malicious PDF — malware analysis report

Static analysis result for SHA-256 e23597464ded7ebf…

MALICIOUS

PDF

78.7 KB Created: 2021-02-22 11:59:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: c15fc58a5063c73f7e213a4b2b043198 SHA-1: 520a1e01e8e041ec5a5feb734f30b9fde49e4a3a SHA-256: e23597464ded7ebfbd55dc52b8cc9b4517d63cc7ac22009d5d57adeb4a242e47
244 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links pointing to external PDF files hosted on various domains, many of which appear to be disposable or used for SEO manipulation. One critical heuristic indicates a link to known malicious redirector infrastructure, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier further support its malicious nature, likely as a phishing lure or a component of a larger attack chain.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/strik?utm_term=yoga+mudra+for+insomnia In PDF document text
    • https://pobolibawawo.weebly.com/uploads/1/3/1/4/131437087/9b3607875d37.pdfIn PDF document text
    • https://juxusuvib.weebly.com/uploads/1/3/0/7/130739690/xuxipinuwopusa_zukodazux.pdfIn PDF document text
    • https://nusisudarebo.weebly.com/uploads/1/3/4/3/134349377/5179170.pdfIn PDF document text
    • https://zadobezaja.weebly.com/uploads/1/3/0/7/130775221/vuweridazuwolom-mufafifoduwav-xagixetanel-nazowowe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408586/normal_603096a470a9b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4474448/normal_5fed5b1943bc9.pdfIn PDF document text
    • http://tekesonisopo.22web.org/gamabovosifinakujisal.pdfIn PDF document text
    • https://gozaxuvo.weebly.com/uploads/1/3/4/6/134612917/zeburimutilu-tijoxifed-zawukubine.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375358/normal_6028e519dc3e6.pdfIn PDF document text
    • https://cdn.sqhk.co/pixorikibam/jFggtUE/xokejipixakulu.pdfIn PDF document text
    • https://cdn.sqhk.co/lojosexotak/ajejhWF/lipipagixesenuradol.pdfIn PDF document text
    • https://wojumujar.weebly.com/uploads/1/3/5/3/135396772/zoxifoliju.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4374852/normal_5fc98cac35a35.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402503/normal_5fe391ec98dc0.pdfIn PDF document text
    • https://kilixezexixoz.weebly.com/uploads/1/3/1/1/131163494/2971887.pdfIn PDF document text
    • https://dojilosadokadog.weebly.com/uploads/1/3/4/8/134890500/dumenif-fukume.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4415304/normal_5ffa7ff77915d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fakuzilezozo.epizy.com/62995404197.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn 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_off0000e694.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE694 6744 bytes
SHA-256: 048fb1891f432488516cd811e7b04d68e7d39e548ca3495625137f8fb0c23ff4
font_01_sfnt_off0000f779.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF779 5156 bytes
SHA-256: fc99b42a43a01251b5cf087d557f777f346e3d6675f32910fd7e35a6e6427748
font_02_sfnt_off000108f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108F1 10716 bytes
SHA-256: aedd478c5096607c4c6054785370e9720287f17c24b88904c836bbe6e4dcb854