Malicious PDF — malware analysis report

Static analysis result for SHA-256 f75ee9b14123420b…

MALICIOUS

PDF

79.4 KB Created: 2021-06-25 20:41:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: a0d4223da9174cd2bddaab3846fdab8a SHA-1: 253675cb2d976dea1ba0705c5b2ef0d670158ee5 SHA-256: f75ee9b14123420baafb43bcde040e903654f951993811352f3017f0c125aa43
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The ML classifier strongly indicated maliciousness, supported by heuristics identifying the PDF as a link farm hosted on compromised WordPress sites. These links likely lead to a second-stage download, as suggested by the PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings. The document body was unreadable, but the presence of numerous links to potentially malicious files on compromised domains points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • 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://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608b68e55abda---90638240578.pdf In PDF document text
    • http://www.urbanwaterways.info/files/vosorolunofajutirigi.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/14d0db38be1746fdd7fb236440e80ba1/64055674542.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/89779613672.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/64327ade5727164b8540b0b59bce891c/95061573815.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/c1c2ccbfa096b86232358eef1e4be40b/batuwedemufo.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/o26gkmh46gri07gq7hhim20hor/64244067474.pdfIn PDF document text
    • https://eravukappalpalli.com/userfiles/file/6552686330.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210606054519.pdfIn PDF document text
    • http://skikk.eu/app/webroot/files/userfiles/files/1604329119.pdfIn PDF document text
    • https://247hvac.ca/fabulous1/uploads/files/nejabesomalukew.pdfIn PDF document text
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/ae2320066d151810c295b44fa067fc83/92352078980.pdfIn PDF document text
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16075500382657---radin.pdfIn PDF document text
    • http://abc-tel.ru/data/File/sivapowele.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-5/20210505065459279618.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/a4f5e0de9b7b94c74a5422f507c6240b/28018633450.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/68697736868.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16094045f0358d---9604230725.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1a1373101---nitesalapakewakigodoris.pdfIn PDF document text
    • https://easybuildapp.com/files/uploaded/files/zubirisisore.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e148c00a63---17624715536.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa53b675e4a---risoxiruv.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6db0156f2---21533364618.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=rdp+session+change+passwordPDF 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_off0000d25a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD25A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA6C 17524 bytes
SHA-256: d9c9f3ef56828b381d3e6466153cbbb8d172d24aac2c80ecebc493339234c654
font_02_sfnt_off00011819.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11819 10780 bytes
SHA-256: 38ba4d498accfc9717a7026529eac448b38b352c259ae35869259597e31502c2