Malicious PDF — malware analysis report

Static analysis result for SHA-256 7af37e3b2dcf9b24…

MALICIOUS

PDF

71.8 KB Created: 2021-03-11 03:52:44 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: b0c8d750d953b51e8fcb8605e4189afc SHA-1: 1cac9024233cf298138732ebccf9c5fa8ee078ff SHA-256: 7af37e3b2dcf9b24948ba04aa2ec185df821a010ec59250b8e12d7d22896074e
186 Risk Score

Malware Insights

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

This PDF file is 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 URLs that point to other PDF documents, likely for SEO manipulation or to distribute further malicious content. The primary IOC is the initial external URI pointing to a search-related URL, which likely leads to the link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://botokaw.ru/award?keyword=bleach+bath+for+eczema+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4417648/normal_6006eca4ebc3f.pdfIn PDF document text
    • https://botakukejase.weebly.com/uploads/1/3/4/6/134610266/tedubuwazad-wufewunep-fagilakobixi-tajavezab.pdfIn PDF document text
    • https://bigudiwox.weebly.com/uploads/1/3/5/3/135304820/7397516.pdfIn PDF document text
    • https://jotozured.weebly.com/uploads/1/3/4/5/134588142/134855.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425760/normal_5fcd651a7d3cd.pdfIn PDF document text
    • https://korudodigujoko.weebly.com/uploads/1/3/0/7/130740169/ef68a.pdfIn PDF document text
    • https://pubedazemel.weebly.com/uploads/1/3/4/8/134870130/2126205.pdfIn PDF document text
    • https://nizevamil.weebly.com/uploads/1/3/2/8/132814567/dedofejoro.pdfIn PDF document text
    • https://lepepapiminokuj.weebly.com/uploads/1/3/4/4/134493398/2499370.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445115/normal_6027b0e6ca449.pdfIn PDF document text
    • https://rojurunonujimos.weebly.com/uploads/1/3/5/3/135325454/c58bc81b17a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380692/normal_5ff7a70d5d321.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462345/normal_5ff366b99ee11.pdfIn PDF document text
    • https://zuzivosojix.weebly.com/uploads/1/3/0/7/130775151/8045180.pdfIn PDF document text
    • https://veriketosamu.weebly.com/uploads/1/3/4/6/134675732/daxovajeb_gozutumizes.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408323/normal_5ffe462489437.pdfIn PDF document text
    • https://jasadugo.weebly.com/uploads/1/3/5/3/135341750/xoninijavuze-zobujifojes-supur.pdfIn PDF document text
    • https://funogefoxareso.weebly.com/uploads/1/3/4/0/134041001/0bb517241d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484995/normal_6020a72b382c0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4405195/normal_5fc622291ff63.pdfIn PDF document text
    • https://merasata.weebly.com/uploads/1/3/1/3/131378960/gawokite.pdfIn PDF document text
    • https://pulezigo.weebly.com/uploads/1/3/4/6/134600697/5583486.pdfIn PDF document text
    • https://meremunodimabak.weebly.com/uploads/1/3/4/5/134516451/8999045.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000dbe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE6 5456 bytes
SHA-256: c91fbc2eb43e01340a58a2023a6614ed455828762ede009846f95f5b67c260e5
font_01_sfnt_off0000ee47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE47 10376 bytes
SHA-256: 9861ee83de1b30566caa92b08cee3465549b384452744d68b23e101a3c151131