Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbff17ef00eb6f5b…

MALICIOUS

PDF

97.1 KB Created: 2021-07-29 17:00:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 807a99cbe7fb5a7e8c4b665208ee8fb7 SHA-1: 0b86ca136cf55c64fca802a0a71bf3c1e0b23e1d SHA-256: cbff17ef00eb6f5b3ba2410ca0673e32b3d0a27b4bee13fcd7ba87f285b42f9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious Link

The PDF document contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of link farms on disposable hosting and compromised sites suggests an attempt to obscure the ultimate destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://kaptenhoki.info/contents//files/nikovixikofita.pdf In PDF document text
    • http://esipro.fr/userfiles/file/xekidasukafemerajubonibok.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/ugnrt539tdr97qluqtgcv1b30s/76940512201.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/01a17ceb78a6ac31e54631ac4d2740b4/7978225029.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/5c6cjt4gk6v6qm9dcbbgl72t0b/jerizovafuk.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/ba0f0cuabfcn3flaibo97l6j37/85378165807.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/71826192947.pdfIn PDF document text
    • https://topinsolventa.ro/userfiles/file/26245196593.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/0uuujcgejlrpjhgj9481u9pknf/xuwarimetopepegorosane.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/94525146729.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0e86ca720---98910409022.pdfIn PDF document text
    • http://targdenunti.ro/userfiles/file/jupofofifepiliwo.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f25295d5eed---totawamijuwizoxu.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4383a7dc90---73155413527.pdfIn PDF document text
    • http://www.srijonihealinghome.com/fckimages/file/10359234925.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zagipedu.pdfIn PDF document text
    • http://greenmodels.ru/uploads/files/42042920386.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fbecbeeab4c---mazirexibubejedetof.pdfIn PDF document text
    • http://helder-effect.nl/userfiles/file/22598426113.pdfIn PDF document text
    • http://memphiscentral1969.com/clients/865565/File/jegosigajujaxoremuziwo.pdfIn PDF document text
    • http://csc0516.com/userfiles/file/20210704114244_x2hsvi.pdfIn PDF document text
    • https://inncredel.com/uploads/fukejawaxi.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6cddd4704---bowudopalozejerokeb.pdfIn PDF document text
    • http://hoggard1975.com/clients/a/a4/a43fc1111b7ad4318f8b553feb79a890/File/24088094281.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/8a1lis4sj8brevnr8ctdiursp5/soxukelunerexugafufet.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/d26ba233c9681baf0d37cc3317db0945/kudezasovakudamawu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=what+is+a+good+summary+for+indeed+resumePDF 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_off0001163d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1163D 17560 bytes
SHA-256: eb104c3e7a1db7d8b8f196297876890d41949bf4c90bc1366ee7ccceb3de800d
font_01_sfnt_off00014466.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14466 10964 bytes
SHA-256: 8f915030686464925a3e2e5a9ac338537ecf109a4aabdceaec0b8fa670468355
font_02_sfnt_off00015d88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1