Malicious PDF — malware analysis report

Static analysis result for SHA-256 398f8ff01d3936bb…

MALICIOUS

PDF

73.5 KB Created: 2021-09-05 00:26:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a65e7a7404fd9720b7de0c1b67739182 SHA-1: 2bd666a6a0bbca2fd4f9857cff0ab5ad72e5103d SHA-256: 398f8ff01d3936bbc313c91baefd1332195e75289c861da69de4e088da02ae28
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a link farm or phishing lure. The 'wkhtmltopdf' metadata indicates it was likely generated programmatically to appear as a document. ClamAV and ML classifiers strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://laborke.ru/uplcv?utm_term=free+english+grammar+worksheet+for+class+2 PDF link annotation
    • http://hanhthien.net/uploads/file/51611156535.pdfIn PDF document text
    • http://axwelindia.com/uploads/23140327573.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6b2fa7e897---kudivuzidijajinominuxaz.pdfIn PDF document text
    • http://artside.org/data/temp/file/gasataturuzesavozino.pdfIn PDF document text
    • https://vocembalo.ch/userfiles/file/mezad.pdfIn PDF document text
    • https://morganmethod.com/ci/userfiles/files/nonone.pdfIn PDF document text
    • http://feriaalainversa.com/uploaded/files/dibulilewademapu.pdfIn PDF document text
    • http://contrast.no/ckfinder/userfiles/files/salifajezorapivuf.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080c3f15adb0---68801781048.pdfIn PDF document text
    • https://arerp.kr/data/file///fereluwafonimewofa.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/4a3191a636f8b3bc931341db1f8ca4ac/41585817346.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0aba59e23---54482672486.pdfIn PDF document text
    • https://www.adilaltinsoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f121ab14d9---jukosakoke.pdfIn PDF document text
    • https://thepainter.asia/upload/files/topivuvagejelu.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1608313db9d0b7---70597025419.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/160c60d262ff1a---juviso.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/sesuzageletelusudiv.pdfIn PDF document text
    • http://grandchainfamilyfoundation.com/clients/85333/File/vegitajajapa.pdfIn PDF document text
    • http://bidwoodmachine.com/d/files/43858652446.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/533btf18u93pr0g2ltqojtu8o7/danukagi.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://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_off0000bd8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD8F 11060 bytes
SHA-256: 0d8fe27587b7f512906db044a03de6ab58f48a4d6846ad7b39d045c84364ad2d
font_01_sfnt_off0000d73a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD73A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4C 15936 bytes
SHA-256: 2b824eecc694cee8fa48b45cd80b36a125405bc2395b8b8ac6c8e11326d1f772