Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3bfa6dc25d885e2…

MALICIOUS

PDF

72.5 KB Created: 2021-09-25 20:27:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a58a90a61dfa499029735ca90c58a7fe SHA-1: 8b856010b96caa89ac14db80f8f99b32f06b2594 SHA-256: c3bfa6dc25d885e2e9b74d6c1d7e2c1a6f9c203640aa1c1b8441584c3017eff3
96 Risk Score

Malware Insights

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

The PDF file was flagged by an ML classifier as malicious. Static analysis revealed it contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting. These links are likely intended to redirect users to download unwanted software or visit malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://oniceh.ru/uplcv?utm_term=tekken+3+android+download+apk PDF link annotation
    • http://joeun-it.com/userData/board/file/tipupa.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/36059979975.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614280e9635c2---51846484675.pdfIn PDF document text
    • http://huarui-bio.com/upload/files/31803721534.pdfIn PDF document text
    • https://nutricount.cz/UserFiles/File/15356714921.pdfIn PDF document text
    • http://kubak-ubezpieczenia.pl/userfiles/file/44499450636.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/mogemaluvisedatobuxuj.pdfIn PDF document text
    • https://skvacations.com/userfiles/file/selalar.pdfIn PDF document text
    • http://www.hzkontejnery.cz/ckfinder/userfiles/files/83629049525.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/53793384521.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/libuzasazusopixote.pdfIn PDF document text
    • http://france-ex.com/images/blog/file/kixijimokisub.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad77364fd4---7463436502.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/wimoguwonuwadopim.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/daduz.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/9b5f7b055e97cca0866b8849c3f461d7/39077323453.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1614afb7f59c9f---lizeninedazabubawi.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/lesawujezetupevanodilupim.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e98be2e9b3---gavawadoverapodiniwepa.pdfIn PDF document text
    • https://onderdurdu.com/upload/ckfinder/files/95377200392.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/madimod.pdfIn PDF document text
    • http://haenuri.net/ckupload/files/zenutu.pdfIn PDF document text
    • https://sanvexe.vn/webroot/img/files/9651717021.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_off0000b6fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6FD 17696 bytes
SHA-256: 797eedc3b65d54804b043e17973539d53f036c703ecf3be1d7100fbc419f75f5
font_01_sfnt_off0000e48c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE48C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fca3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA3 10432 bytes
SHA-256: 52c444a641989dc379d2bda09b1d6be7608a70a2f4b57196b178c2007af93d02