Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbe992f657aac5a0…

MALICIOUS

PDF

86.5 KB Created: 2021-07-06 13:57:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 97d65815b5f3d3de6758d9a48d21e4df SHA-1: c9aebe79531ab68115ebb8ecda7820972ad1a524 SHA-256: cbe992f657aac5a053f7b2306172ed03f6857347b968b33398934f2107b0d879
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous links to external websites, many hosted on compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd8fb94611---78125916911.pdf In PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/3a93e4ab8af682ef9f2d3302e62c9e9f/favodabixipije.pdfIn PDF document text
    • http://france-ex.com/images/blog//file/58739020565.pdfIn PDF document text
    • https://italvaping.com/file/nubelovuxe.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160873599dacde---xokewabafazelujupu.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/70747513334.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///53887788938.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4b3bc11ec---wizuzuzusewalejat.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/kuxipogupoxakipasiv.pdfIn PDF document text
    • http://familiehollander.nl/images/uploadedimages/file/baxulot.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/xumirigijebimulozerutape.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c87dd371f8c---62433095381.pdfIn PDF document text
    • http://balassalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/96195558587.pdfIn PDF document text
    • http://gwardiajuvenia.pl/zdjecia/fck/file/78322940383.pdfIn PDF document text
    • https://icbacademy.com/upload/files/liliworasubobok.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/3d00e179be3e8edae88b7df4bc676240/turazumebafuloji.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4a5073e3f---sutod.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/xubope.pdfIn PDF document text
    • http://drironcat.com/images/file/nimik.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/eegussathf6bfjvpr8shhj348i/kokikikuromidisetodimuvej.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16085fbf2b686c---gijosoniritixaraloponuraf.pdfIn PDF document text
    • https://argumentua.com/i/file/28702350985.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/tl2ptsdbguik9369ahf7mfg4k0/mifejegoxikekosasa.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/defalurivuliviforova.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160959aa040370---73725309692.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/26e5445061b5c147235ba80ef58bb6e3/43506981105.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=what+colors+to+mix+to+make+dark+bluePDF 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_off0000ed05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED05 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010517.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10517 17456 bytes
SHA-256: e3e3c47e9e9e28c4ac0073d2ad364ca12cc97195aa46075b683d49ab75608292
font_02_sfnt_off0001333f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1333F 10956 bytes
SHA-256: d68d54c8a1d42522aa616aa80cc8d0e5a8c86388d43b533712e06beab2170d45