Malicious PDF — malware analysis report

Static analysis result for SHA-256 da57131266512f9e…

MALICIOUS

PDF

81.8 KB Created: 2021-09-08 23:11:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f0d58e276b6cf99f0eae3d5856920562 SHA-1: eee4ac0422837c65ef192f3548fdcb798cc8b655 SHA-256: da57131266512f9e97cbda9225f96c66c43112f6fe493f99f21624a96b30953c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites hosting other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of embedded URLs and link farm heuristics confirms the attack pattern of directing users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613323c70e7b6---vivosukuribifol.pdf In PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/dcfa2c40180cd908663dd3f9e5a2881d/52396912340.pdfIn PDF document text
    • https://granitabrasive.ro/editor_up/dudulidovuvomevowen.pdfIn PDF document text
    • https://onderhoudnlgarantie.nl/upload/file/sovave.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/44998117244.pdfIn PDF document text
    • http://eggtesting.com/admin/uploads/file/femefepuwametajoronasa.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137b72a107ee---zanagefegokejumovekibakip.pdfIn PDF document text
    • http://smcertificationservices.com/userfiles/files/lusagubobibudaf.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161308262da32c---16435583693.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/xizogilikujenepalukudu.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613244fc929e8---52678833651.pdfIn PDF document text
    • https://purmoradiatoriai.lt/images/files/rabapewaputiraxokev.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/68330474461.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16132f9af959f1---50164729613.pdfIn PDF document text
    • http://thementalhealthadvocates.org/files/userfiles/file/nonuzedadanodexikonelurin.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/fb396d282b8c4a1301b23e6da8bb90e7/jaforilez.pdfIn PDF document text
    • http://eamenfaraz.com/cache/fck_files/file/55438214224.pdfIn PDF document text
    • https://uangraja.com/contents/files/mukogipevaxosokafisolora.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16136437943d7e---dasexoke.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/e6cd091d7c0099ef5f205562dae5e2a6/sotiw.pdfIn PDF document text
    • http://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/9141506579.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/4b8377242d7de77584298f5c2df6ee4f/14821176241.pdfIn PDF document text
    • http://gddfboiler.com/uploads/files/kovide.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/98037736719.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=justice+league+snyder+streamPDF 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_off0000d99b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD99B 18316 bytes
SHA-256: ac3c44abf5a2a93373cd18c3751f97cf2863694479055424a7cef5bd212f0951
font_01_sfnt_off000108fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108FC 10796 bytes
SHA-256: b501e1b6ce5fdacb59754a880f029fe071da00ce4087dbc4e3ef3e22a49090f8
font_02_sfnt_off000121b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1