Malicious PDF — malware analysis report

Static analysis result for SHA-256 5af0846e58c838fd…

MALICIOUS

PDF

81.1 KB Created: 2021-09-04 13:50:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9ecfbabcdc09e1d926b19c5040ecb436 SHA-1: aea530c7f03f492c397d8e06d969a276c7eabc0d SHA-256: 5af0846e58c838fd3fbfe1fe06cbd9a2306f7bcb923babc67ba31e4bee3a9ea7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of a link farm hosted on disposable or compromised domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

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://krisoc.ru/uplcv?utm_term=el+existencialismo+es+un+humanismo+pdf+gratis PDF link annotation
    • http://xn--xhq021fvrwdth.com/d/files/paveta.pdfIn PDF document text
    • http://impex-italia.it/userfiles/files/pokuxidakumigovamuviza.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/lunudasuwelolerererisefap.pdfIn PDF document text
    • https://elegune.net/files/galeria/files/zevet.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/16081e071b8472---83813427730.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/8211655945.pdfIn PDF document text
    • https://noddy.nu/images/file/nuvovavopiki.pdfIn PDF document text
    • http://123podkrovie.sk/editor_uploads/files/41476311399.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16077300e3fe1e---82233757813.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/39142420088.pdfIn PDF document text
    • http://mrpennarak.com/user_file/file/79528884206.pdfIn PDF document text
    • http://fouladsazanco.com/Upload/file/vepomevubogejik.pdfIn PDF document text
    • https://llibreriaha.com/img/events/file/gomuk.pdfIn PDF document text
    • http://kaies.net/upfiles/2108261244351485632rmj10.pdfIn PDF document text
    • http://train-in-japan.com/images/blog//file/fidogiwog.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/67457296884.pdfIn PDF document text
    • https://upaspor.com/resimler/files/raram.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612757faebd1f---xoxakafelatexisifazu.pdfIn PDF document text
    • http://dh-cell.com/ckfinder/userfiles/files/74587287727.pdfIn PDF document text
    • http://fratellilongoni.com/userfiles/files/26651498081.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/dilurujuxarikasiwibu.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160cc08dcedd04---8099361150.pdfIn PDF document text
    • http://matchonusa.com/uploads/files/43665090302.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_off0000d1a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A0 19292 bytes
SHA-256: 71f4ba1c33be1544c563d58d931d4db2d16b04d39e3d4f07e178923cdfb3dfda
font_01_sfnt_off000102fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102FA 11252 bytes
SHA-256: 2c811d370af660c9e181c17214035795bc4b81c8f122d5121f5b6c70b5fd96d8
font_02_sfnt_off00011cf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1