Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b981472f6f6b706…

MALICIOUS

PDF

82.7 KB Created: 2021-09-23 07:52:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 81b7644f321aa059b279772627cc19d8 SHA-1: c495b755ad54f7dd18d980d0edafc209e9a1cd1c SHA-256: 8b981472f6f6b7066c01719aa3f2e4b32acf4fef27416b55b3b9df714557d296
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. It contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • 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 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 http://nawoo.net/userData/board/file/bowowuzoka.pdf In PDF document text
    • http://firewaterdamagedfw.com/test/fckeditor/uploadfiles/file/61716937238.pdfIn PDF document text
    • http://uralcomservis.ru/crn_fls/crn_files/xomuvizojikisesijudo.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/64ij3v23iane9faf68spbr4ae5/pivez.pdfIn PDF document text
    • http://safiorida.dk/operatori/userfiles/file/54687696503.pdfIn PDF document text
    • https://eminencesolutions.in/resources/userfiles/file/jidekugowonugin.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/15678934747.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/98683594251.pdfIn PDF document text
    • http://aotwresort.org/ckfinder/userfiles/files/jefukopi.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/wikusogifulabu.pdfIn PDF document text
    • https://bistakalikotenetwork.com/userfiles/file/gagow.pdfIn PDF document text
    • http://sissonne.hu/editor_up/95455111034.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210916_093536.pdfIn PDF document text
    • https://bccphil.paramedix.biz/uploadfiles/file/87002900807.pdfIn PDF document text
    • http://eksternest.be/images/file/72725035247.pdfIn PDF document text
    • https://renewone.de/files/likawa.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/161331199bb87f---2640754438.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/48093989303.pdfIn PDF document text
    • http://cafesezony.ru/fck_editor_files/files/movakedolosed.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/pimexaded.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021090704361173499.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/76000744122.pdfIn PDF document text
    • http://matrixpaint.com/ckfinder/userfiles/files/zufibeteruketobafevuzape.pdfIn PDF document text
    • https://betentour.com/sites/default/files/file/42094568520.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=android+built+in+call+recorderPDF link annotation
    • 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://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_off0000db3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB3D 10416 bytes
SHA-256: d06c9f019e6f8d190a4c969ac77ee76caa31e36209996b128549dd4fe1a83fc5
font_01_sfnt_off0000f2f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B03 19436 bytes
SHA-256: d6770581f1b08b7cd33bbde772b4b47f9b3e30861bb36b2e6a7cc8eaedec523e