Malicious PDF — malware analysis report

Static analysis result for SHA-256 35c08e99d5258a4b…

MALICIOUS

PDF

91.4 KB Created: 2021-06-29 06:56:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bdde054d32f586525107c610be87f08c SHA-1: b9789dff7a4aa09a8fd15374168d840603bbc429 SHA-256: 35c08e99d5258a4b087beb67f86ad6d46e016210cb58c761a82e1c4393f86950
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This suggests a multi-stage attack, likely for phishing or malware delivery. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were directly extracted, the structure and URL patterns are consistent with known phishing and malware distribution techniques.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a18848a5127---debofapanewabalopu.pdf In PDF document text
    • https://najlepsze-w-polsce.pl/uploads/24237443495.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606fde3fd240a---78034403151.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16090eaccf1cad---22304106339.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c87fea6805---39100866803.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/da5a71c41927653150114f67da1c2718/19999431403.pdfIn PDF document text
    • https://associazionedynamica.it/uploads/file/ramesepitin.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/9396129b6eda2a119e996a98d0e160b3/39287380582.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/b8sft52499jr3v22jgcjr5ndo2/dedagaludopa.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/papego.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/r7ifbrl5tuhv4ueup9d8lr0od4/zebopevisixaluxesotukoti.pdfIn PDF document text
    • https://didacostruzioni.it/userfiles/file/67879483692.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a262b07e3b1---56162491779.pdfIn PDF document text
    • https://ascinfratech.com/clientprojects/trading/file/zudidelesunuwaxe.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5018689c02---96590674147.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=the+godfather+ps2+manualPDF 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_off0000fde6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDE6 11036 bytes
SHA-256: 27b1f1de05070da287efca254ed7d51ff19b8cf61c5a494d86039c0f7dd2378d
font_01_sfnt_off00011748.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11748 18808 bytes
SHA-256: 3a44296ee430ea77eafa50e6e23f50cb08fec1cb695d5b317185398959e35415
font_02_sfnt_off000147dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1