Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb35c565d80f86ab…

MALICIOUS

PDF

71.7 KB Created: 2021-06-05 09:54:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: f94bb4b4b0c96c0b88a0afd47c5e6d43 SHA-1: 48cb044fffac7bbfb83e9ca80d4c3b9d9f8e1df1 SHA-256: cb35c565d80f86abe7059194a242ffb2c449e91fe554fdc7d12140878142bfd8
186 Risk Score

Malware Insights

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

This PDF document functions as a link farm, directing users to numerous external PDF files hosted on disposable domains. The primary lure appears to be a search result for a technical query, aiming to trick users into clicking through to potentially malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://infrive.ru/pbw?utm_term=how+do+i+change+my+casio+calculator+to+radians PDF link annotation
    • https://bamojatiw.weebly.com/uploads/1/3/4/6/134699288/2108371.pdfIn PDF document text
    • https://musimisipamorek.weebly.com/uploads/1/3/4/5/134594646/1c06da1b6.pdfIn PDF document text
    • https://gosasaweju.weebly.com/uploads/1/3/1/3/131384289/xidovonozinas.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457014/normal_5fcebbc12b8f8.pdfIn PDF document text
    • https://zekuwatifakaxi.weebly.com/uploads/1/3/2/8/132815855/lufisigixexexiz.pdfIn PDF document text
    • https://koditagonuxu.weebly.com/uploads/1/3/5/3/135339835/58aa1a80a52440.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4372719/normal_5ff9e8532b669.pdfIn PDF document text
    • https://pinuwolaterogus.weebly.com/uploads/1/3/5/9/135957395/zidapikufumup.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481055/normal_5fd82532cafe7.pdfIn PDF document text
    • https://kuvukodu.weebly.com/uploads/1/3/1/4/131453249/90680c6ed0.pdfIn PDF document text
    • https://gewilowada.weebly.com/uploads/1/3/0/7/130776716/cf07ac.pdfIn PDF document text
    • https://zopixidasopotid.weebly.com/uploads/1/3/1/3/131397955/7e1be23e74ace.pdfIn PDF document text
    • https://redodire.weebly.com/uploads/1/3/1/4/131408340/wubogisapefo.pdfIn PDF document text
    • https://jumuwubugunitus.weebly.com/uploads/1/3/1/0/131070493/wugubode.pdfIn PDF document text
    • https://rukinedofixod.weebly.com/uploads/1/3/4/3/134348838/5689300.pdfIn PDF document text
    • https://siropenisawad.weebly.com/uploads/1/3/4/3/134353493/xufosuxotew.pdfIn PDF document text
    • https://nizufamira.weebly.com/uploads/1/3/4/3/134310662/ca50a.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/93358dd8-2968-4454-8b8d-2bfe7f6e8865/6929081027.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c47e322e-3591-4692-a37c-6a27c127cb64/is_there_gonna_be_tintin_2.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9041f6f-2bc7-4250-a3e4-2060ebbc322e/jaxarin.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/18caa04d-3b3f-4689-8c07-ada7fc9a94d7/laxurowaloxalugiger.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_off0000da25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA25 5508 bytes
SHA-256: 1d696195d3002101616a03dfc9fd136880f6da204a0efe3b2ca4914b43449fda
font_01_sfnt_off0000eccd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECCD 10584 bytes
SHA-256: ea1faede72b52bf7b902cb5f35c10bf0363e28ddbc917e712fa635f440bec538