Malicious PDF — malware analysis report

Static analysis result for SHA-256 615b93ddcb0b4d2f…

MALICIOUS

PDF

79.9 KB Created: 2021-09-12 02:25:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2b3008cf5eb88835c394043196640605 SHA-1: be638b590bebec8274c619abcb54845962a333bd SHA-256: 615b93ddcb0b4d2fedd9469349c14f13c17cdf2e189ffca854876dcb9ee6130a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various domains, many of which are associated with compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://krisoc.ru/uplcv?utm_term=extreme+landings+apk+download PDF link annotation
    • http://artin-intranet.com/ckupload/files/joludukosuzexubozag.pdfIn PDF document text
    • http://idcla.net/upload/files/52580850618.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/xabinebafujas.pdfIn PDF document text
    • http://logicparcel.net/uploadsEditorfile/fiwawejapufemaxixat.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/161314acda66b9---61463693037.pdfIn PDF document text
    • http://plenerowe.kbo.pl/ckfinder/userfiles/files/xojepudabulimoxepo.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a899b1766c---miwufejuxezikogu.pdfIn PDF document text
    • http://canadapremiumlubes.com/survey/userfiles/files/bezesabuvo.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/11265889151.pdfIn PDF document text
    • http://moskvaznaet.ru/upload/files/wejewisaboz.pdfIn PDF document text
    • https://officialbacknumber.com/editor_up/xaxibe.pdfIn PDF document text
    • http://vdadanang.vn/app/webroot/assets/files/notiwusinowosofomi.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/86757839583.pdfIn PDF document text
    • http://rcsiprojectracker.com/userfiles/files/rulumusuwulosixapuko.pdfIn PDF document text
    • http://wonsakai.com/uploads/files/wefutumelofipurebe.pdfIn PDF document text
    • http://archpiudue.com/userfiles/files/zababemiloj.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/xoxevogono.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/161381e7ff0617---311953558.pdfIn PDF document text
    • https://aayams.com/userfiles/file/naferazojojigorikakikevin.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5665b24df---34177131345.pdfIn PDF document text
    • http://fashionflutters.com/ckfinder/userfiles/files/kalijupovanusutojeriseju.pdfIn PDF document text
    • https://dhesient.com/media/diwudumozizojutewuwile.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_off0000d493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD493 16992 bytes
SHA-256: 68d8384c3c18ad67a8a2ea4c0e136aaca7d3f37e5359c6acdcecaff3a52ad2c9
font_01_sfnt_off0001009f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1009F 10996 bytes
SHA-256: 626e5a1e27d0580ceed777350558fc8c8ac800fc38947a30b2723607be208625
font_02_sfnt_off000119fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1