Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd3b732c041a3d75…

MALICIOUS

PDF

88.3 KB Created: 2021-07-15 19:11:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: a5b6613953bdd14c6207d67a5ed5cbf7 SHA-1: 1633619214b530ef32d7f9df94bef5f6c940712d SHA-256: cd3b732c041a3d75715b841b0d107a789b7ef1f8f0de675d6d08584f5b817828
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised websites, many of which host other PDF files, suggesting a link farm or distribution network. The presence of a 'download button' heuristic and the ML classifier's high confidence score indicate malicious intent. The document's structure and embedded links point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/4c61214f42fbbd7e5d0ac43b571798bf/xezoxuxobewerof.pdf In PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/me0bk8pf36likobbhtujef6ehv/71175542762.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/e1eda2ce85fb93722a373e8926f4fbd4/77340311743.pdfIn PDF document text
    • https://gregor-biffiger.ch/userfiles/file/47197032228.pdfIn PDF document text
    • http://mxagproducts.com/upload/browse/file/jomumosol.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a36cf5817b2---kabanifaxexif.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/f165ebab2e55917d9e4f02dbc0b069c4/wapilerafeves.pdfIn PDF document text
    • https://agermag.ro/mm/file/79979045968.pdfIn PDF document text
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/c24522be15dcb7758ced974e8a636be3/potaribuvebidekuta.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a38266193d4---93018036316.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/lvucj42ioj21qv0vm0sne99i7d/bisekexizuriduvesonav.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/7b4e6b41d633c09e5794ed79d69b3490/navaba.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160ae00165235a---fabamenigewezevepewovuxid.pdfIn PDF document text
    • http://nsdadventist.org/FCKData/file/85481015217.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/c3e9e6ae56846c64577049598e0cf14a/pavilonorepewidefimat.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2930df03a3---gesizujukebowameta.pdfIn PDF document text
    • http://ahsaipu.com/v15/Upload/file/20215131556248361.pdfIn PDF document text
    • https://ivanamihic.com//files/fateromekebomul.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/ovgbsah1knhj9a89kfud0ltmss/18845130556.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/89288247188.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160786ab57015d---zanetogebifivitomabe.pdfIn PDF document text
    • https://www.hmgfinance.com/ckfinder/userfiles/files/47065486813.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=download+frozen+2+full+movie+for+freePDF link annotation
    • http://pro.ovh.net/~tribuene/images/banque/file/rovebatezowakukalotobe.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_off0000f729.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF729 10684 bytes
SHA-256: 5d703fd90586ebd00cf5fe01f3e793e0facbb003fd97454659669e251b997cae
font_01_sfnt_off00010fbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127CF 16912 bytes
SHA-256: 0b057b02831958a143f330c9d5f52aac5089adafb0c8e8b41561857a65d3e461