Malicious PDF — malware analysis report

Static analysis result for SHA-256 4caa66a3f9fdcc44…

MALICIOUS

PDF

89.5 KB Created: 2021-07-16 03:48:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 46917d122af5df735fe508980960dba5 SHA-1: e80aadc3cf5e85a0cf13b53ca5a32edafa2fef37 SHA-256: 4caa66a3f9fdcc444d2279992087ef2711ffdd6832e00c0528df5ee3fdd7041f
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The ML classifier and PDF link farm heuristics strongly indicate malicious intent. The document contains numerous external links, many pointing to PDF files hosted on various domains, some of which are associated with compromised CMS uploads. This suggests the PDF is used to redirect users to potentially malicious content or for SEO poisoning.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 https://xn--fiqa735be48e.com/upload/files/bizewiwidak.pdf In PDF document text
    • https://thepainter.asia/upload/files/39136813983.pdfIn PDF document text
    • http://russkiivopros.com/images/FCKeditor/file/55696383308.pdfIn PDF document text
    • http://saintthomasmonrovia.org/clients/a/a7/a774d5b45fc75aba9c6fcf07501e1e58/File/73320647475.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609022d71571a---favimexopepawuzefo.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/3a72a0f39f278d7a537d875aa7b9480c/vutodupexutavuri.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/bifipovorewoxawoloval.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/174324546.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/97195952460.pdfIn PDF document text
    • https://samsungdvmklima.com/upload/ckfinder/files/taxera.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/mibifaterozamilajozuvivu.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/togidokineripe.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c6c00186c---65447438190.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/tvfnkrlum3dpeda2r82v5qvkul/23995571243.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a6eb86f1c93---rureturerawi.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160772e341d7a1---75215459282.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c46ee848a1---23370277576.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/7b345l43uqvt3ub0bb7rbj1uo1/xigomejob.pdfIn PDF document text
    • https://evermoral.hk/upload/file/1625829465.pdfIn PDF document text
    • https://mertlakustika.cz/images/pages/file/20106373064.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/3533400305.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=happy+11th+wedding+anniversary+to+usPDF 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_off0000fa30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA30 11036 bytes
SHA-256: 449c98e2537137a4b927d5967b183edeaba5d816267c8dd439398f6f6a30f35c
font_01_sfnt_off000113b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113B6 17336 bytes
SHA-256: f43dd51a958858e0c3080bfc97a43142ddf28c04d1463887958607b8491bb80e
font_02_sfnt_off000140d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140D8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1