Malicious PDF — malware analysis report

Static analysis result for SHA-256 2135ec8c242443ef…

MALICIOUS

PDF

94.4 KB Created: 2021-06-30 11:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 70e7bf43e66e8892633c19d00a542375 SHA-1: 35676f3407edc2d3d5d27bd197426b508343d120 SHA-256: 2135ec8c242443ef76ee29b2cffaee69f1e1f14ba597fad57213f90c8a7d0b22
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The presence of compromised CMS upload links further supports a malicious distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/u1veaui75qpdu9v5jl7lik93r1/sevogexugovojimokosir.pdf In PDF document text
    • https://pet-fashion.ro/mm/file/libapexodekopuxi.pdfIn PDF document text
    • https://thehero88vip.com/ckfinder/images_store/files/10585770749.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/lijukowamaginejutuvapugav.pdfIn PDF document text
    • http://gernano.eu/gfx/userfiles/files/suwofile.pdfIn PDF document text
    • http://xn--h49avwqct32ewe967crscpsaz7d.com/ckupload/files/75709487137.pdfIn PDF document text
    • http://haai.org/upload/file/86405541001.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/jekazibipata.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/vokabugupilurefeki.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16092713aca08a---5073443615.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/952f4ac8e4a9737055b59b91a87f82da/gigisovi.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/84ad7191fa9c8ec79be4e02a0cd09d39/pinodi.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/4804071008.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cff1481bc17---tazizojumap.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7714f870bf---vixupobu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=tell+me+about+yourself+for+fresher+examplesPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f94b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF94B 16820 bytes
SHA-256: a02b711752166cd5082faa11166a4d6326a02b18099a14d2f7011b8faf911189
font_01_sfnt_off00012517.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12517 16392 bytes
SHA-256: 439f91fc52918ec11de7c10fc66f42d556e3ca0baf24f0cec7590a9fe4e8f18d
font_02_sfnt_off00013b45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B45 10848 bytes
SHA-256: d9d0720972a02993832f90ed0fd10692a427b7e86aebdb689218e387a0ba46ff
font_03_sfnt_off00015438.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15438 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1