Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f668cca5e60549…

MALICIOUS

PDF

93.1 KB Created: 2021-08-05 18:54:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8f7e7aaf6439ccb2c1997ade87c63fa3 SHA-1: 913692841d5fb592614d43ded561e46d63c8ef0e SHA-256: 28f668cca5e60549d3d3d2f658d7d3f18c2e396e5a48aa5aabce33a82e57789b
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS upload storage, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e6277bd13---diligovugob.pdf In PDF document text
    • http://altiro.nl/home/tjerk/file/lonuxataneluvubopogo.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/v9v6qmjrgo7iqgtjkpbdkjoj9a/fekobopiva.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/53051b4aed77dc73113c0ac0715c639a/mosuxemonejafatara.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0811144dd8---lesut.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/7b2e62c6df322284eb9eb3cd162ef90e/95657397547.pdfIn PDF document text
    • https://campermagazine.tv/public/file/25247903309.pdfIn PDF document text
    • http://bennett-legal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nusivoxo.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/26304170875.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/pojafivetujimalipep.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/498b1597be2cb7283dd41c9abce49680/dotepebuxuvebetewose.pdfIn PDF document text
    • https://triyoga-tv.ru/userfiles/file/83669392536.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/9b7ba91204b53ea74bc1efbe5f866303/85544471106.pdfIn PDF document text
    • https://censcakmu.org/board/file/files/rulazejijole.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160717a1049dce---bumoloveburijax.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/kolapefirevanezod.pdfIn PDF document text
    • http://asfus.net/virgsurv/userfiles/file/67348158226.pdfIn PDF document text
    • http://bocghedanang.com/media/ftp/file/32261744036.pdfIn PDF document text
    • http://hotelpenza58.ru/ckfinder/userfiles/files/28202185781.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607210ad34b64---lexesade.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/09cc37f0ee9ca1253a3633dd225845be/58337425561.pdfIn PDF document text
    • https://dunakanyarfesto.hu/ckfinder/userfiles/files/sikureludogo.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160be43463d94c---lugidefule.pdfIn PDF document text
    • https://cherrychile.cl/cherry/uploads/contenido/files/nekufedogobufotav.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=best+army+templates+hoi4PDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/fizisitaletegikap.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_off0001041f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1041F 10660 bytes
SHA-256: cd8504c6936bcbfd20a5a01822046d6df14b84fb3975efad05a0f2c87a5de79b
font_01_sfnt_off00011ca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000134b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134B7 18512 bytes
SHA-256: 50d6e70885704f221cc68dd9fb6b7d44258c9cb7754bd6c7cafdc90f09bf2b2a