Malicious PDF — malware analysis report

Static analysis result for SHA-256 956cea3eeb9b9d1b…

MALICIOUS

PDF

85.6 KB Created: 2021-08-21 08:29:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 41c3c73a3bbc343e5bba46f3e19aa4b4 SHA-1: 16ea023d7437154519e487f8b184d4cce9986032 SHA-256: 956cea3eeb9b9d1b64d1033aa5e45a2095235ba6bd0c41b1c4e5124dba5d7cc6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to websites that appear to be using compromised CMS upload directories. The ML classifier strongly indicates maliciousness. While no scripts were directly extracted, the structure suggests a link farm designed to redirect users to potentially malicious sites, possibly for SEO spam or to host further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 http://theheavent.com/userfiles/files/3034552585.pdf In PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160bd88cdb603d---tujudukelixugalapixabavi.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/dd625963b1f3e56b26cc2c67de6bf150/69968006159.pdfIn PDF document text
    • http://petrduchek.com/files/ramosirefirotim.pdfIn PDF document text
    • https://pieseautocomenzi.ro/userfiles/file/93746229797.pdfIn PDF document text
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160716f386e8ce---xagazusolome.pdfIn PDF document text
    • http://sendedianqi.com/upload_fck/file/2021-6-29/20210629235554983086.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/ae0tubd7nob4d5l8bra1jmibqp/39289898138.pdfIn PDF document text
    • https://ntc-container.com/upload/files/mosonex.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161004af753f66---58545373598.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/gefixagawis.pdfIn PDF document text
    • http://skncn.com/u/files/remasazeroboxajopefamofab.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16080e471abd42---xolizoze.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce677a7fdd4---jukoxefevimit.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/b81176bd31b7e1de62caf4f1906d1789/33402538729.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/puxamazasomupikaj.pdfIn PDF document text
    • https://yaofangpeixun.com/upload/files/mugubivor.pdfIn PDF document text
    • http://erdivigado.hu/userkepek/file/31957717701.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9e7ad41d19---rofan.pdfIn PDF document text
    • https://at1-turbo-j3t.com/contents//files/23296273152.pdfIn PDF document text
    • https://hydratrend.com/application/third_party/ckfinder/userfiles/files/kedomajemepukev.pdfIn PDF document text
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/35552188907.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=what+is+the+main+purpose+for+comparison+and+contrast+brainlyPDF 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_off0000e849.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE849 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10060 11232 bytes
SHA-256: cf7052f5ad91d20ff6b921bb8f2b574bc500dfc91edf0f62a01c2dacd1b7bccf
font_02_sfnt_off00011a46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A46 17212 bytes
SHA-256: 4e6a0dc2cdb3fe076dc2ee9d0d31a40f9d3370bde9e81ebe280b3a27f4f4c52f