Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e93def997e5a822…

MALICIOUS

PDF

78.3 KB Created: 2021-03-10 14:01:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: bc61e034035c0915464056210901487a SHA-1: 2e6f94ef73d417476d75c96b8387d678952a6c8a SHA-256: 4e93def997e5a8227d9e1ed604269963beb1078277888060b6838a533e984eda
126 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or redirection scheme. One prominent URL, https://xezojetit.ru/strik?utm_term=book+raving+fans+summary, is directly embedded and likely serves as the initial lure. The ML classifier strongly indicates maliciousness, and the overall structure points to an attempt to drive traffic to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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://xezojetit.ru/strik?utm_term=book+raving+fans+summary PDF link annotation
    • https://tarakemutelomul.weebly.com/uploads/1/3/2/3/132303353/wasudirorut.pdfIn PDF document text
    • https://metubunotawe.weebly.com/uploads/1/3/4/5/134595280/soxiremowow_neriwagaj_sodamisar_fobexivituvinur.pdfIn PDF document text
    • https://xalitive.weebly.com/uploads/1/3/4/3/134320973/feruguzetoto.pdfIn PDF document text
    • https://sekotujuf.weebly.com/uploads/1/3/5/9/135960234/wewovabu.pdfIn PDF document text
    • https://zovuwiveja.weebly.com/uploads/1/3/4/8/134880504/pokusilo.pdfIn PDF document text
    • https://kezofufilulo.weebly.com/uploads/1/3/4/4/134488682/korizigapesoxad.pdfIn PDF document text
    • https://rudanivaxaf.weebly.com/uploads/1/3/4/4/134497940/e20231164cac40.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/62dabf82-125e-4e33-a80b-12008fd6833d/61709815192.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5b7e8ce9-f7b3-4763-a555-42b211a74cc7/40202443827.pdfIn PDF document text
    • https://97783159-ced7-426e-9fbd-60d2bb3342fb.filesusr.com/ugd/00058f_aa2660f951d248ecbf0a815fb941bc67.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/fa75f7ad-c7ac-48f4-bf8a-040b5911588b/what_are_the_advantages_of_bilingualism_in_childhood.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/096d5ecf-0696-467a-8507-ac541f491c1a/is_the_hp_stream_11_a_good_laptop.pdfIn PDF document text
    • https://315736c7-1030-4200-8d24-05c9f4951019.filesusr.com/ugd/d19ca0_e89214de045b4afcab012153e1625264.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9a003d2e-bae7-488e-9b63-23c8b8ba14cd/titulevokumofizapaw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1bee0f4d-adbf-4bec-bf84-071a94cb1d0d/77085850803.pdfIn PDF document text
    • https://s3.amazonaws.com/fokapikow/lifeporujodu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f01b50f-60fe-420c-bb1c-d27e642e4ddf/91448303819.pdfIn PDF document text
    • https://78ff948a-0765-49f5-a22c-0fbe0eba7848.filesusr.com/ugd/888d0b_da2ae777d806445ba5a77fe7adf8ce27.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1cecd83d-a05a-47c2-a4b7-eb58da7b55d9/50651424238.pdfIn PDF document text
    • https://3c4962d9-41f7-4f14-8396-dad57cc8de20.filesusr.com/ugd/a2de88_bf77ba4dbcd54e589a72817b0d634ae5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/184e5b0d-57f3-4d59-a536-978ed314a66b/lanizuvusorebirojokuwikun.pdfIn PDF document text
    • https://336ddc11-c37d-4cd6-9685-7accad2975f7.filesusr.com/ugd/479fa9_7ae257b247094e3287c36814dd960c08.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tobovunoberiki/22598144738.pdfIn PDF document text
    • https://s3.amazonaws.com/xopugup/xobazumutosukegizun.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D1 5328 bytes
SHA-256: 64da511f8fe23bdf319cd9c6ce32db7ea3a384a02ae6dec995dab71bc2cab836
font_01_sfnt_off000106fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106FB 10848 bytes
SHA-256: 9c676a538370614e769d985d60c0832a26190ff267e6fb3d1ebc1c41b0297d11