Malicious PDF — malware analysis report

Static analysis result for SHA-256 add90f3860b83ac1…

MALICIOUS

PDF

69.8 KB Created: 2021-09-26 08:33:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4d90aa527d20d7284c025bd0cb9e3c1b SHA-1: fc60e042ddb2ab6bc87b374533088f6b796e9f61 SHA-256: add90f3860b83ac1011fbc3b7e2778ef5a453ede43991328a3d4025f146ea219
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, suggesting the document is part of a link farm designed to evade detection and distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://catamma.ru/uplcv?utm_term=android+push+notification+no+sound PDF link annotation
    • http://diysmart.net/userfiles/file/jexizekiroxitev.pdfIn PDF document text
    • https://enilubricant.hoakhanh.vn/uploads/image/files/dafafarewekojijegogavi.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/75954850239.pdfIn PDF document text
    • https://greenlandpark.com/uploads/files/depogixis.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/bugibos.pdfIn PDF document text
    • https://5udua.com/contents/files/turuwiz.pdfIn PDF document text
    • http://aescantabria.es/upload/fckeditor/file///63843879237.pdfIn PDF document text
    • http://ceresasrl.it/userfiles/files/weketabogot.pdfIn PDF document text
    • http://lezeckastenakosice.sk/upload/files/16176315583.pdfIn PDF document text
    • http://tz5168.com/uploadfile/image/2021/09/23/file/20210923_034652_169.pdfIn PDF document text
    • http://koreadramatour.com/FileData/ckfinder/files/20210912_CF06766E75BE0962.pdfIn PDF document text
    • http://website-design-company.in/dev3/damodar/ckfinder/core/connector/php/userfiles/files/lavop.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/b7a9858287ba824631735e5cbe6a55f2/56401831536.pdfIn PDF document text
    • http://chinamakina.com/userfiles/file/7574825433.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/35958679301.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140ea8386cfd---xokadilopuponowezu.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202109251628428517.pdfIn PDF document text
    • http://grupafurman.pl/!mag2011/userfiles/file/mikulakateg.pdfIn PDF document text
    • https://arnetbilgisayar.com/upload/ckfinder/files/gugonidesajegiselo.pdfIn PDF document text
    • http://tsuiteru66.com/userfiles/file/fatabafujewavuzikuxibafal.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613967ed042bb---51716195191.pdfIn PDF document text
    • http://spartaksedlec.cz/spartaksedlec/userfiles/file/45140568806.pdfIn PDF document text
    • http://ashole.hu/UserFiles/File/66426231108.pdfIn PDF document text
    • http://111-orte.com/testarea/cwsCMSlight/media/files/kokezurawabobe.pdfIn PDF document text
    • 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_off0000b181.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB181 10620 bytes
SHA-256: 579c25d1df1e8d68e7b9c2e767e6d6c4b7d952e8239b25f2d37a4d84db7f25d8
font_01_sfnt_off0000c9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e1d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D5 14948 bytes
SHA-256: f8f71a82d2e128e08dca1370c8d08dea66c8e401ee8b071989ce9649e0405ef9