Malicious PDF — malware analysis report

Static analysis result for SHA-256 8390d3b1947e2f6d…

MALICIOUS

PDF

92.6 KB Created: 2021-06-28 03:48:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4883d5aea778c7d0eca9c30636a69c62 SHA-1: bef2489226bc5fee9d6ae11314f38a317831ad9a SHA-256: 8390d3b1947e2f6df1429ba3c7a23300b705aadf2d2eff2342e73c4403fe4f90
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various websites, many of which appear to be hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure as a link farm on disposable hosting further supports this assessment.

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
  • 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=kenny+chesneys+marriages
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/pirolipasi.pdf
    • https://aiwatopup.com/ckfinder/userfiles/files/68628505002.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160814d3b17e6f---28629807074.pdf
    • http://aostavet.it/userfiles/files/pawosumip.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ee2964a574---tugixagar.pdf
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/d798fdc8fc291fbbc0b33b17f5862fa5/77116741708.pdf
    • http://adria-ex.com/images/blog//file/66931519317.pdf
    • https://1877painters.com/FCKeditor/file/48405023561.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c2b2291143---75894039381.pdf
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/4b92f98c365f22cf2d89168ebe3cf462/66478567267.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1029c4c2f---68144044745.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c631eed7f04---musabivitelaxob.pdf
    • http://soft-pro.hr/upload/datoteke/57444944313.pdf
    • http://adaviestransportltd.com/userfiles/file/dijomidekarififamevig.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16078dc0f58b1c---kumepoxaseweka.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fd10307bf0---pesidowasoku.pdf
    • https://hohsingfiber.com/ufiles/files/78463938070.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c1019ace8af---5942870669.pdf
    • http://usateatop.com/_upload/files/dufexozivebovu.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16083d59371291---rugujowolejoxijomibatusop.pdf
    • http://americanewbie.com/userfiles/file/63292709517.pdf
    • http://billedbutikken.dk/articlefiles/file/dugaledetowabef.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001092a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1092A 16792 bytes
font_01_sfnt_off0001213c.bin
89274e9952374cef90b09e39c740877ca7e350cb02abc21bd3009f222f391cf0
pdf-font-stream PDF embedded font (sfnt) at offset 0x1213C 17204 bytes
font_02_sfnt_off00014de4.bin
410bf7add2a3bfeb56128c345cbffba75688b93a1d939f85ae7e5e67c6518fd1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14DE4 10520 bytes