Malicious PDF — malware analysis report

Static analysis result for SHA-256 15516ed0dd937baa…

MALICIOUS

PDF

83.0 KB Created: 2021-09-06 04:24:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 09eec0e1a95e4d3892731fbcb3c73641 SHA-1: b08370eaafcc296f3f4d01329bec780fbff0d505 SHA-256: 15516ed0dd937baaf0d491075d96a2c897a069008418a447f032ebaecf96c9ea
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 WordPress sites acting as link farms. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest the document is designed to direct users to potentially malicious or SEO-poisoned content. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f451016cef---98103148727.pdf In PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869b1e1f75e---varorekuzukone.pdfIn PDF document text
    • https://www.htlexpress.com/ckfinder/userfiles/files/9821152838.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097ee1d0f3a3---55616739104.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/d0b3a5d15709068baf91a68b542ac115/lafixijakowageno.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/rexatibalomosoz.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f8dfe84414e---19415727837.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210730030858.pdfIn PDF document text
    • https://www.latentoac.com/portal/wp-content/plugins/super-forms/uploads/php/files/eisei8611da64ham7gkmmfnj51/mosunumep.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af9a1b3fca8---75348415850.pdfIn PDF document text
    • https://www.fishhabitatnetwork.com.au/application/third_party/ckfinder/userfiles/files/pegimusatoxezewate.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c92b6ae88e---7470202648.pdfIn PDF document text
    • https://samowar.ch/upload/file/84539579739.pdfIn PDF document text
    • http://starma.pl/files/file/sesuru.pdfIn PDF document text
    • http://z-i-f.ru/userfiles/file/20104593130.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/02141fb62d721b2292004b73be604740/wakeda.pdfIn PDF document text
    • http://cosmik-kino.ru/sadm_files/73819205793.pdfIn PDF document text
    • https://tskrea.com/userfiles/file/14514648934.pdfIn PDF document text
    • https://basealimentare.it/webroot/files/fck_uploads/File/77293757192.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16098438958c50---93870872829.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=taipei+train+station+map+pdfPDF 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_off0000dd3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF551 18696 bytes
SHA-256: f23baca943e7e5415d4a161455f701abdda2c32c19a7d7857f8e56fbca3d2831
font_02_sfnt_off0001263a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1263A 10576 bytes
SHA-256: 4eba31a8d51e6d7399ad13b32f3e8a0d1ed369383f4061253e7249d77d6c2ad5