Malicious PDF — malware analysis report

Static analysis result for SHA-256 25a271fc3c4f1087…

MALICIOUS

PDF

77.7 KB Created: 2021-03-29 13:33:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: beff646b906d4e169e89b639b693cbe1 SHA-1: b2fa5807cdb8f014bc5821be947de9c12c3ac71b SHA-256: 25a271fc3c4f10870fb488b95cb2a827dbe863a20c37732a8b961ad7a968acd4
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, many pointing to disposable hosting, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a large number of outbound links designed to appear as search results. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution.

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://seumenha.ru/award?keyword=mac+preview+pdf+form+change+font+size PDF link annotation
    • https://xomivevisavuwog.weebly.com/uploads/1/3/4/8/134852088/jutowabukidorar_betojixukepabi.pdfIn PDF document text
    • http://cabinetsly.xyz/what_are_the_codes_of_conductk7gf6.pdfIn PDF document text
    • https://cdn.sqhk.co/mexovaru/geig6nc/rewok.pdfIn PDF document text
    • https://dojibabebane.weebly.com/uploads/1/3/2/6/132682208/wenavufir.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386095/normal_6052459446524.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468540/normal_6020d622b8141.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385612/normal_5ffa67507e156.pdfIn PDF document text
    • https://losanuritajog.weebly.com/uploads/1/3/4/7/134730792/23734f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418399/normal_5fca67dbee119.pdfIn PDF document text
    • https://cdn.sqhk.co/buzulexoxuve/bgAjhT0/kafixirezef.pdfIn PDF document text
    • http://trendmobile.ru/gurejewizimosimuvfeyb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://dd7ee03d-3646-4e01-a1e1-4c0a7e2c9e57.filesusr.com/ugd/d7ba0f_e1f1567d46574480aea3de574f2a918e.pdf?index=trueIn PDF document text
    • https://9e2b3e3a-6a02-4d3b-8ba9-5acc01041672.filesusr.com/ugd/66c878_7280500c498840538762d03bcac87a52.pdf?index=trueIn PDF document text
    • https://f0198b83-f3fe-41b4-8315-bacd7eabb238.filesusr.com/ugd/2b3f46_9f5297041e6c4ff2b7ca28dde34399d5.pdf?index=trueIn PDF document text
    • https://00eaa6b3-f026-4720-b00f-fafb40066352.filesusr.com/ugd/d498be_b4fbc0ccd5c14a1a939f790db356a62d.pdf?index=trueIn PDF document text
    • https://ad060920-74d0-4a59-a46a-f478898ed72a.filesusr.com/ugd/a7c1e6_85503efa26cb461a8c0d392a316d048a.pdf?index=trueIn PDF document text
    • https://5d3a3edc-1384-4eb0-a354-174dd54c13aa.filesusr.com/ugd/7f5dc5_5ffb69ee50d647ef9571e191b49b4c5e.pdf?index=trueIn PDF document text
    • https://90e68d66-75cd-4f9f-aa76-03b1e6b67b4d.filesusr.com/ugd/324cd8_9dae2f599a1c4843b40dc1ff6a31d5e1.pdf?index=trueIn PDF document text
    • https://a804c8a8-fdf7-4fba-b19b-c23aecc29597.filesusr.com/ugd/a7074a_b5bdc2d74e7a4d889cdcdc2d36f1ecc7.pdf?index=trueIn PDF document text
    • https://77a80da1-97a3-4b40-ba11-54c6d232eb66.filesusr.com/ugd/39a0fd_e3f4fc619ad9422fb58954b8ba5b5f08.pdf?index=trueIn 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_off0000f14b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF14B 5744 bytes
SHA-256: 0812d28a026980a01686370e383f8aba60f5b2780f878a2cf708e5067465697f
font_01_sfnt_off000104e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E1 10816 bytes
SHA-256: a52e114c34b4ac8bffa8d7023276129f0735b631e4afc2094f29fe72cc0b8da0