Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd60cb0a84a12c0a…

MALICIOUS

PDF

84.2 KB Created: 2021-06-25 12:20:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1ad8f48f32d2552273e5e3c1d59ae1dd SHA-1: 68f14426bb35e9e754aaa943d3f42591127ee264 SHA-256: bd60cb0a84a12c0a04c82027ecdcff21a3aa2d558f37339cc768de0b1bb88e8f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a link farm pointing to multiple compromised WordPress upload directories and disposable hosting sites, indicating an attempt to obscure the final destination of malicious links. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the nature of the link farm and the detection results point towards a common technique for distributing malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://tai-yang.tw/taiyang/upload/file/49431096380.pdf In PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1bfcabfb5---niruve.pdfIn PDF document text
    • https://samoinstitute.mn/uploads/assets/file/86715865745.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/7297a6ffd80bde7920f58fb7da237e85/47470410401.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/nbgevqn28q956hodj1fr9butr0/duvasalogaxiwupov.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/pozokosubomiteko.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608234f64137d---sosuxisa.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/kgvgfg3p565bq819oj4ogpt9lv/52471302202.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1607bfedc65405---kapiz.pdfIn PDF document text
    • https://anpheatingandac.com/nbloom/fckuploads/file/8996117745.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/mvs4ihsgfotuqcvak1luitl395/92137768531.pdfIn PDF document text
    • http://arch-teh.com/pic/userfile/rofurifefazokirugati.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///15192939262.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160764513956a0---xudavibidugemunovevi.pdfIn PDF document text
    • http://www.heksan.com.pl/file/gepejixepilivezaxujuteku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=prova+do+ita+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_off0000e4d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fceb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCEB 19048 bytes
SHA-256: 959d73e64937f20f22e604af51dce167bf5e8304832876182e0c33f916883917
font_02_sfnt_off00012c58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C58 10108 bytes
SHA-256: 4a23469ddd61977032cf4ac99de321a5dc56f56a0a3cee082d96495dc88d6b61