Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c4a9eadb8ea72a2…

MALICIOUS

PDF

83.5 KB Created: 2021-08-14 23:02:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2af28941d6a265d1d77554f96caab64c SHA-1: cb8b9d574279fe323eb4c0b1b1352b978d08052c SHA-256: 8c4a9eadb8ea72a22c050d8000e06cf5112c84459d2f583e233b617b5a4eb3b8
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier strongly indicates maliciousness. The embedded JavaScript and link farm structure suggest an attempt to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/r88etri3eevjqe9q36qg38p2mv/kiduperenub.pdf In PDF document text
    • http://webinaris.blog/ckfinder/userfiles/publics/files/makum.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/95783065385.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/31191391758.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b963eb0a299---63907831548.pdfIn PDF document text
    • https://nasikampung.info/contents//files/41853653826.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/5e93ff3ee14644bd3d6a44e7450104be/9127100229.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-7-20/20210720233903319319.pdfIn PDF document text
    • http://suphammamnon.org/uploads/files/boloxujewegalezeluwisije.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/4vk9aob8l941u3l278s1862vt5/zunorobigoro.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/d6q3vvars6phvg7mrdfa8cdtbv/65200399619.pdfIn PDF document text
    • http://bouncebodysupplements.com/newerac2c/userfiles/file/gezapowozoduv.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/568a44b95809a988a4425babc7659a8c/85953992167.pdfIn PDF document text
    • http://brooklynsmokeshops.com/admin/images/file/40335771687.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/bdcdc01f13dd1e8dfe1d95b8747dc764/81097680016.pdfIn PDF document text
    • http://albarossa.jp/js/upload/files/11358004818.pdfIn PDF document text
    • http://chonburi33.com/userfiles/file/32317656436.pdfIn PDF document text
    • https://gastrotest.co/ckfinder/userfiles/files/60667793729.pdfIn PDF document text
    • http://cjmjwarrickhudsonfamilyreunion.com/clients/9/9b/9be434dcd9982d5451de1b36a82eb828/File/ponusebodegawalix.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/fewuzodibezonupav.pdfIn PDF document text
    • https://autotrans911.com/thread/admin/uploads/file/rizulozesovobabiwulun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=rogue+galaxy+insectron+locationsPDF 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_off0000e004.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE004 17988 bytes
SHA-256: 840fdae3f6c5715ea868c241eea9f36448ab967615425be65ddc97cc297f0fa5
font_01_sfnt_off00010cd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CD2 10764 bytes
SHA-256: 42baba7b71b333bd4dce7c7be2e705b0526fa22b96920b9182e23a99ee0925c1
font_02_sfnt_off000125cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1