Malicious PDF — malware analysis report

Static analysis result for SHA-256 b192ba036d2e987f…

MALICIOUS

PDF

81.5 KB Created: 2021-04-02 00:58:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 009295588864a64023707f91e37f9bdd SHA-1: 84fc93bd60015173f8ed4f84aee708493d0cccdf SHA-256: b192ba036d2e987fd06e859118436fbda81294f1c442f557d379d524edf687d4
126 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, as indicated by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier also strongly flagged this PDF as malicious. The primary purpose appears to be SEO manipulation or distributing links to potentially malicious content, rather than a direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://bologen.ru/123?utm_term=linear+algebra+for+machine+learning+cheat+sheet PDF link annotation
    • https://lojamagimom.weebly.com/uploads/1/3/0/9/130969840/mibow.pdfIn PDF document text
    • https://zitudoxe.weebly.com/uploads/1/3/1/4/131437236/buwumotimi.pdfIn PDF document text
    • https://ragulifogikub.weebly.com/uploads/1/3/3/9/133986704/ccc006.pdfIn PDF document text
    • http://nnorm-id.com/numero_de_carte_bancaire_validep8nbo.pdfIn PDF document text
    • https://nunosutelakib.weebly.com/uploads/1/3/1/3/131383720/3464303.pdfIn PDF document text
    • https://sopaxibifezubin.weebly.com/uploads/1/3/4/6/134608036/5543385.pdfIn PDF document text
    • https://mavitebe.weebly.com/uploads/1/3/1/1/131163983/kanar-vemokon-bokimoboruveri.pdfIn PDF document text
    • https://saworajopasu.weebly.com/uploads/1/3/0/7/130775294/5007657.pdfIn PDF document text
    • http://help-violation.com/does_brandsmart_open_on_thanksgivingz4dc3.pdfIn PDF document text
    • https://vusugurubem.weebly.com/uploads/1/3/0/9/130969976/duzugewuxiroloj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://eb40363d-1d1f-4170-a897-f23f0f433116.filesusr.com/ugd/2a1429_6c2b327dfb2848c99b035f06a932c54e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a5cc85b-7799-4296-b6d0-89b3d1004957/62360149664.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b9130175-e465-420c-905b-aaefe0bb555d/42285481367.pdfIn PDF document text
    • https://e4034479-4ead-418b-af8c-5be8dc72bdbe.filesusr.com/ugd/1e8759_62053003a74e47cfb7a4d165bc582630.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1f697dd-4cde-4d59-8b0a-1a664df0ccbc/gawube.pdfIn PDF document text
    • https://01c19f78-c7d0-441a-b56a-8672493f87de.filesusr.com/ugd/9d66c7_4b6c98fbf2e2404687a3ba0b4f36457b.pdf?index=trueIn PDF document text
    • https://387a498e-9551-4239-9507-3183ba214552.filesusr.com/ugd/cd403b_4ab5726ff7ca4260a396cbb376077519.pdf?index=trueIn PDF document text
    • https://d5e9a058-cbdc-4968-ba72-30cdbf1e36a3.filesusr.com/ugd/9cfd0a_1ed6a6d0e8d44ea48b5ad1a75cf3d574.pdf?index=trueIn PDF document text
    • https://3c2b787d-8465-4662-bdcc-bf736d584291.filesusr.com/ugd/8760e7_281d839aba3549d4adc170d7e137317d.pdf?index=trueIn PDF document text
    • https://7fe1f042-206b-4735-a408-f56337efeeb4.filesusr.com/ugd/d34b51_2edfa65a67634049aeaaa54adf8fdf76.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_off00010048.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10048 5376 bytes
SHA-256: 02e59ae4a42da4479545a16c49391b7c3bed16cbc176b4aa4e76dd620aef64d1
font_01_sfnt_off0001126f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1126F 11256 bytes
SHA-256: 736e1fc5ce6d951962547ab1e82afb2e971e4ffddb1cc5acc9174dc8e3376882