Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1c5350c3b30c30a…

MALICIOUS

PDF

88.2 KB Created: 2021-05-29 15:06:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 9e1d4dd19650211bf937d135952467f3 SHA-1: 549026b51ae8165c63af610ee906c833fe26ef91 SHA-256: e1c5350c3b30c30a0d7e54f693b49467f81e1c2a5342b40d01c2d9f8cae247b9
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://mezovuduw.ru/strik?utm_term=toefl+itp+reading+comprehension+practice+test+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4475730/normal_604fc0599ad2f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445324/normal_6045faefde33d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4444370/normal_5fe1ca5bcb350.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461777/normal_604d207869a94.pdfIn PDF document text
    • https://begosibaluta.weebly.com/uploads/1/3/0/7/130775163/nutewukorapenax.pdfIn PDF document text
    • https://tetalopen.weebly.com/uploads/1/3/1/8/131857308/5d04e232d1c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471109/normal_60256e764fcf6.pdfIn PDF document text
    • https://dupemokuko.weebly.com/uploads/1/3/4/7/134759865/517605.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415308/normal_60605659ac6bf.pdfIn PDF document text
    • https://didirivex.weebly.com/uploads/1/3/4/2/134265945/sajewirijugikaxutoxa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462374/normal_6049c85f7956a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471959/normal_60581fa6b00c6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386591/normal_604d2e66c9888.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384159/normal_5fda0f831e9ac.pdfIn PDF document text
    • https://mabavelege.weebly.com/uploads/1/3/0/7/130775551/xudataxa-pumipemuxeke-zexogedim-liwepugixawalig.pdfIn PDF document text
    • https://godewofevi.weebly.com/uploads/1/3/2/8/132814364/1679800.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459177/normal_60499a29c5fb8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501996/normal_602b49d7db13e.pdfIn PDF document text
    • https://jonubafepap.weebly.com/uploads/1/3/4/7/134737483/xiripaxeriv_resikolosatigow.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/003040c9-04da-4aa5-8228-0694a2b005d2/which_is_more_difficult_civil_or_mechanical_engineering.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ae3a675f-2104-45ef-9d02-1afc7edfeee8/objects_first_with_java_6th_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ac46a8dd-e4fe-405f-811b-15b0c8e9699e/vetativan.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001068f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1068F 5516 bytes
SHA-256: adc50bf8184b784fbd14017c4390300b00494e9b0d406c12945ecc4474a8a817
font_01_sfnt_off0001192b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1192B 10652 bytes
SHA-256: a065fc0ded1fd3d3c42f9176085f8ba268c331fb9bf3e7e6b0b5a5805cac13c1
font_02_sfnt_off00013da1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DA1 16144 bytes
SHA-256: 2a5f1667c2e343500efde63e3dd6a136498333968b1680966ac5eb34589f1174