Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d9b56adfbd03217…

MALICIOUS

PDF

83.1 KB Created: 2021-09-07 18:33:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 019cfc98ece768d372bdc6432e21fdeb SHA-1: 9117337a7baa725101c4245ef0055ddb60f8b1fb SHA-256: 8d9b56adfbd0321703dae924db9b8d3f2b592c20d931855b449fb56476eabdd7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of SEO manipulation or directing traffic to potentially malicious sites. No scripts were extracted, but the overall structure and URL distribution strongly suggest a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://serramentisiciliano.it/userfiles/files/novebuxojuxefef.pdf In PDF document text
    • https://hagepoorter.be/files/files/48410574198.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210522182339526544062m7a.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/a7a6fc58bd96d1ac64b84b8c204fb5a1/rerifetabezamifozub.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/butepitabalamarifogibo.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a09c006d7b2---22530611765.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/8865387088.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805fb677bdb---32596647796.pdfIn PDF document text
    • https://uangraja.com/contents//files/doxozug.pdfIn PDF document text
    • https://trouver-une-ssii.com/img/pics/files/98947497780.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/5e09acfa545b12352646967270765f94/bobowarinam.pdfIn PDF document text
    • https://jackinthegymtpe.com/uploads/files/202108271535301087.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/vlhhf7d0r90t9o2fbdv9j5bsb0/99432614061.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072aa5cc4853---51876436063.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b6d9be846e0---tavekodimas.pdfIn PDF document text
    • https://mobilieroccasion.fr/uploads/file/32866717053.pdfIn PDF document text
    • http://michardardillier.com/ckfinder/userfiles/files/zaxesozosa.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c97fd2eb43f---50969429543.pdfIn PDF document text
    • https://marljivo.hr/userfiles/file/40936741281.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/72369216727.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/56207bb4df7b2de24b5bfce6bbd70e38/82923758970.pdfIn PDF document text
    • http://gerocuki.hu/user/file/xogezezovowuk.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/vuget.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/33947709917.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b185f8aad7---mipemezimexadekoteliw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=danubio+azul+partitura+para+piano+pdfPDF 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_off0000d954.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD954 10492 bytes
SHA-256: c3ca2a084fa17c27fec4e92536a06c6fbac3c36a4da6e9138c3cb903ebfc1774
font_01_sfnt_off0000f107.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF107 20984 bytes
SHA-256: c1b7920e095907b39823240f9faee1222e77176b6a7bb80d8c56bfacb1d7ba29
font_02_sfnt_off000126b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1