Malicious PDF — malware analysis report

Static analysis result for SHA-256 935b679dc4952bfd…

MALICIOUS

PDF

73.4 KB Created: 2021-09-20 01:54:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9c921bd3f340fe5bb280589dd3a5c219 SHA-1: 0d7e24e39de229f51f33cfaeb2c3cf06b7c2ec90 SHA-256: 935b679dc4952bfd2528e6c38cddec415e35cc8e71d4e0b4c6d5be65148d5c56
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with a critical heuristic firing for PDF_JS indicating embedded JavaScript. This JavaScript is likely responsible for redirecting the user to external URLs, such as the one found at 'https://wastran.ru/uplcv?utm_term=mario+tennis+nintendo+64+rom', which is characteristic of phishing or malware distribution campaigns. The PDF also contains a high number of external URIs, suggesting a link farm or redirection strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://wastran.ru/uplcv?utm_term=mario+tennis+nintendo+64+rom PDF link annotation
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/bb38402f783050e16c03820945cc33da/97206486717.pdfIn PDF document text
    • http://nc-israel.ru/upload/files/virikimijefurelafikos.pdfIn PDF document text
    • http://bpabv.nl/uploadfiles/file/tawarapaguguxoxirazo.pdfIn PDF document text
    • https://psihodesk.ro/ckfinder/userfiles/files/vefilefizatekafiren.pdfIn PDF document text
    • http://dentalweek.eu/userfiles/files/jemetufimuv.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/9817134751.pdfIn PDF document text
    • https://bem-sa.com/img/file/3285547270.pdfIn PDF document text
    • https://promenade-perpignan.com/userfiles/file/98196846778.pdfIn PDF document text
    • http://domkomplekt34.ru/attachments/file/45906039743.pdfIn PDF document text
    • http://hzeiger.com/userfiles/file/lulopovilijunokefojogo.pdfIn PDF document text
    • http://mqskin.com/luutru/files/55086304390.pdfIn PDF document text
    • http://easyliveconstruction.com/ci/userfiles/files/benefaromasokapubonisi.pdfIn PDF document text
    • http://kingsauto-bar.com/js/upload/files/81257938656.pdfIn PDF document text
    • https://adikkeempat.com/contents/files/muxejejoxusexaminosa.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///53794839631.pdfIn PDF document text
    • http://huarui-bio.com/upload/files/mokol.pdfIn PDF document text
    • http://alfatreyd-mebel.ru/archive/images/file/34334375735.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/161442b8f7a070---tegepopenagixiz.pdfIn PDF document text
    • http://sgrappresentanze.eu/userfiles/files/pumixexutipegefuvowefe.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/98911787865.pdfIn PDF document text
    • http://hyunbulsa.org/~ewedd2/userfiles/file/71654836222.pdfIn PDF document text
    • http://fioredda.com/userfiles/files/66555727151.pdfIn PDF document text
    • https://grupo.iberia.com/js/ckfinder/userfiles/files/muzabodejupaganenojefor.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_off0000b928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB928 10600 bytes
SHA-256: 8d28d8a8e1b441c20cb1877ea57236853843e37543d383f781e49ce3be397be9
font_01_sfnt_off0000d170.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD170 17592 bytes
SHA-256: 8e6d8b69e00156109bf76256c06b04ccb1f28d0a0638c3b705d9e8ac4d850e69
font_02_sfnt_off0000fed7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFED7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1