Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b4ce86b7a6c4632…

MALICIOUS

PDF

82.6 KB Created: 2021-09-08 20:50:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a40146ee5ad7d870803c200a0d237d1d SHA-1: f167521eac86c5000914a4cdc667d68629c3b575 SHA-256: 6b4ce86b7a6c4632e1f4c3610fa24006ad4de4d9d34fdad24a9ed9029bc2dfd7
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple external URLs, many of which are hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The structure suggests it's an attachment delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://alpasol.e-giant.net/upload/files/kuvol.pdf In PDF document text
    • https://gionggiacam.gagiongvitgiong.com/ckfinder/userfiles/files/livudamavudekozekosuzites.pdfIn PDF document text
    • http://circolonauticofavignana.it/userfiles/files/63966560588.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/13981806398.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210908_103713.pdfIn PDF document text
    • https://hanomanberjaya.com/contents/files/39633951368.pdfIn PDF document text
    • http://nguoigiupviec99.com/webroot/img/files/tumuvomag.pdfIn PDF document text
    • http://bilafafafa.com/shopadmin/upload/files/73934940692.pdfIn PDF document text
    • http://sk-uralstroy.ru/uploads/files/tisas.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/47558239518.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/211f7a1357cea11e086bfea5475aaf11/duwugarejasojag.pdfIn PDF document text
    • https://sealskinz.ru/files/file/48601651062.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161318f480438c---17576402920.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/e87645e3e35a592e1a26025be954f879/zelevedikafem.pdfIn PDF document text
    • https://www.willmarshelter.com/ckfinder/userfiles/files/29822384173.pdfIn PDF document text
    • https://miltonmattox.com/userfiles/file/60438940489.pdfIn PDF document text
    • http://studiolauramoschini.it/userfiles/files/movewewifidanovevawo.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/i0udb5i22qmm2kcd5ienjl80hc/wilidetat.pdfIn PDF document text
    • http://noxsun.com/jingkelun/userfiles/files/20210904130355.pdfIn PDF document text
    • http://studiotecnicoligioni.com/userfiles/files/pudevub.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/9804836937.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/19711088746.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=the+celebrated+jumping+frog+pdfPDF 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_off0000dba9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA9 11232 bytes
SHA-256: df590987d32d9ab2dc9edce91c95960770012fcf9c56ecf5b6081806c079fa2f
font_01_sfnt_off0000f552.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF552 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D64 18396 bytes
SHA-256: f4c21096cea2e14fff21dcad3509a104ba302b3ad11134d590761cb6d71c9b8e