Malicious PDF — malware analysis report

Static analysis result for SHA-256 b10cfbc362d76cfe…

MALICIOUS

PDF

83.8 KB Created: 2021-07-25 09:28:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 904757845fea17f6beff4590b9358651 SHA-1: 8ebde5d5ed57aec23e9fe4e59b29645b2170de9a SHA-256: b10cfbc362d76cfef63d613d3b8daddc56f60285e68076cd6a8d5bcded9c028d
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, suggesting an attempt to manipulate search engine results or lure users to malicious sites. The ML classifier strongly flags this PDF as malicious, supporting the conclusion that it is designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607d506a5623d---48531936398.pdf In PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/16093f4fda213c---bububazavodozojiwib.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/59232389741.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9f9a295b35---73938385049.pdfIn PDF document text
    • https://vmwarts.com/ecovic/file/10270967308.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160aca8377dae9---74172472654.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/70543711803.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/822ej2vtn2m9ulrkuldcl4ajvv/24467016874.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d24052afa---49427449872.pdfIn PDF document text
    • http://banghaija.com/userfiles/file/wimejejo.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160740341dd029---taxikepujufeluxitexixet.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1a577a6a0f---duresafupuja.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/90934087285.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/a5ec2580a4ccf57acb76ee5a4d9387a0/7019571438.pdfIn PDF document text
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/kosawupetufisizewavab.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/249196r56lun3vngkcvof5f3nd/lonozabarudug.pdfIn PDF document text
    • http://pelesiuvalymas.lt/i/File/kimuji.pdfIn PDF document text
    • http://versobrokers.eu/userfiles/files/52437798990.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609eb75b6962e---41897752961.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=adb+driver+install+windows+7+32+bitPDF 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_off0000e2c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2C9 17284 bytes
SHA-256: 146ac6761e8262de4ca7655dcc2ee15b0368cb37a8d4f536227d48ab35dddc9f
font_01_sfnt_off0001104c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1104C 10856 bytes
SHA-256: 18714e913dc6ebedd6c601c798b20bf7fef834647ce60040a462929b85a7ba05
font_02_sfnt_off000129b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1