Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8c93d25b3af6b51…

MALICIOUS

PDF

79.8 KB Created: 2021-09-10 13:58:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 74933977adc47ae3094a39276a11b36b SHA-1: 5f8d8df587eeb57e41e5f6c77669db7cc5729f8a SHA-256: f8c93d25b3af6b518cb03cb559bdcb9ba57f805bb16fb8f10b20b7210ea70ca2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The structure suggests a link farm designed to obscure the ultimate destination of the user's click.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://archism.ru/uplcv?utm_term=android+text+font+family PDF link annotation
    • http://fs-select.com/images/blog/file/72641981274.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5a3b1e84a---sarazopafutiguwanuw.pdfIn PDF document text
    • https://073741256.com/uploads/files/202109071605401661.pdfIn PDF document text
    • http://jrecchina.com/ckeditor/ckfinder/userfiles/files/tegavaxi.pdfIn PDF document text
    • http://creaorganization.com/depo/sayfaresim/file/37280302334.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5d0a1e737---49196259822.pdfIn PDF document text
    • http://baharev76.ru/userfiles/file/jexato.pdfIn PDF document text
    • http://ozhelalikram.de/resimler/files/349447806.pdfIn PDF document text
    • http://uticachemical.com/files/upload/files/30768140409.pdfIn PDF document text
    • http://preciz.com/uploads/wysiwyg/files/71404168872.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/q5l2eh6qeeb7tubm71cqabb0ij/xefuzi.pdfIn PDF document text
    • http://wittymall.com/multimedia/userfiles/file/6525898270.pdfIn PDF document text
    • https://avukatwebsitesi.kocgrafik.net/upload/files/puxevumusixiwapitajefi.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a88d95ae9---konedadaxomibotajuzato.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/tipanaxiwolegalivafal.pdfIn PDF document text
    • http://qkmedica.com/uploads/userfiles/file/32916530906.pdfIn PDF document text
    • http://77owship.netsociality.com/upload/files/bokilujipilaf.pdfIn PDF document text
    • https://xcheck.vn/uploads/userfiles/file/pagijiguj.pdfIn PDF document text
    • http://kingsfci.com/userfiles/file/40617940961.pdfIn PDF document text
    • https://www.hkha.org/ckfinder/userfiles/files/gazesipu.pdfIn PDF document text
    • http://sententtech.com/file_media/file_image/file/kexewixunusasexabowud.pdfIn PDF document text
    • http://dar-tom.pl/userfiles/file/50771999707.pdfIn PDF document text
    • http://togul.org/sites/default/files/file/wapireguw.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_off0000d252.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD252 18332 bytes
SHA-256: 2589642e54d79c27358b713729ee01a2861990db7eeae06031a7642825e5372a
font_01_sfnt_off00010192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10192 10544 bytes
SHA-256: 4e60d4e5d7c9aab22529cbf50004451144d7de583e46b1c81ac82130adf03b3e
font_02_sfnt_off0001199c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1199C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1