Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f1f33646511cec7…

MALICIOUS

PDF

87.5 KB Created: 2021-09-05 21:50:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9cb657854888bc6473b5279bc979f913 SHA-1: d079366b272330ec4bea7a34ade1bcf6c75dbc98 SHA-256: 1f1f33646511cec784aba6d2916df9204bdf68178582e0082d5974b7e3af5653
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/907762c2057eec219bba276d1e08b3bb/4934644572.pdf In PDF document text
    • http://mgocsm.in/userfiles/file/78077912935.pdfIn PDF document text
    • https://telewebmarketing.com/FCKeditor/file/nujigamamuf.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/4bf0e02796b6dbd36eaab686cd9ace49/burolozo.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aba4b32f20b---xopowim.pdfIn PDF document text
    • http://dainichiji.com/upload_ckr/files/zezigekanozuviniraf.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/jekunagugowol.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/61515185179.pdfIn PDF document text
    • https://mcrlclient.gilcom.ro/ckfinder/userfiles/files/84264595740.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/6e577786364ce9bba9bd6800d2495ccb/85101101082.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/ae2s0u7g8vf0v2rqs8slb71m9a/53575305404.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/16087fa1cd624e---xaninonabu.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160fd26f3cd916---92011480622.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160764b58cff6c---25684268570.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/45828053889.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/51696988851.pdfIn PDF document text
    • http://makassitools.com/userfiles/file///84524003821.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/d3c1efb5121df2fe339953f9f2b6bffa/42595291197.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ff0d641392e---pimebakupasawafosu.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d4ccf0d573d---72047206736.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160de6f3632760---80222167248.pdfIn PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/42604467833.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///49200027209.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/26k3d8aajf5g63iruajf1k4jt7/dulujipum.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=tratamiento+nutricional+en+varices+esofagicas+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_off0000ecf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECF8 11092 bytes
SHA-256: f25ac3f5eb7b658cafb9c57f6ba5d58935b3ed4715aae379c867f6939aae86db
font_01_sfnt_off000106a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A5 18680 bytes
SHA-256: 7bdf06d6ae0ceffb25973af936c46231d921585deb0e5649e9a801142075eba5
font_02_sfnt_off000135f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1