Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dd6419c366c6ad9…

MALICIOUS

PDF

69.7 KB Created: 2021-10-03 19:29:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6aa6fe3a778d59fac2c8cff48f0f0f4d SHA-1: 437303f7fee486de65bc74302c8659b8bdc3cd5c SHA-256: 8dd6419c366c6ad9cc830d0be0b27e03936369736e3fe986a244e09e7d0679a7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to external resources, some hosted on compromised CMS uploads. ClamAV detection and ML classification strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 7

  • 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.
  • 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://synerhu.ru/uplcv?utm_term=universal+absorbent+pads
    • http://caratow.be/userfiles/file/40476321526.pdf
    • http://ahjygjg.com/upload_fck/file/2021-9-23/20210923010708173697.pdf
    • http://gintaras.cz/userfiles/file/91523292801.pdf
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/meret.pdf
    • https://mandaljeebanking.in/ckfinder/userfiles/files/67140224752.pdf
    • http://metall-press.ru/files/dujeluvawawo.pdf
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/8f764d35a4e735c812412f77669d94ad/90962386016.pdf
    • http://www.coverseg.com/uploads/ckfinder/files/26655647639.pdf
    • https://sakkestadbil.no/userfiles/file/88868268522.pdf
    • https://zaragozadenoche.es/upload/files/dujupud.pdf
    • https://qian-ho.com/upfiles/editor/files/puzakezalasox.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16151bd1fbd979---fujebadumaxez.pdf
    • http://jrmhandling.nl/upload/file/25946412617.pdf
    • https://dalnoboy.com/data/filestorage/upload/files/wekexer.pdf
    • https://sunnyrosesschool.com/userfiles/file/banasebisorufow.pdf
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/36899869015.pdf
    • https://mentormedya.com/files/33461822446.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138bb91cd32b---99219976119.pdf
    • https://kildevangen.dk/files/49450898938.pdf
    • http://apartmany.cucoriedka.sk/data/files/80764281680.pdf
    • https://avistravel.activsport.ro/userfiles/file/fedexidekesekijulod.pdf
    • https://volandovia.it/public/fileeditor/file/gozafizukesovagugag.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_off0000b064.bin
d58a30d9cd2713f97001d144f7b876198773277e42aae029af032c2f398a2203
pdf-font-stream PDF embedded font (sfnt) at offset 0xB064 10600 bytes
font_01_sfnt_off0000c883.bin
720f2ca2b16f5503d75b78061db1b0469186612112406b36d9c82d63af1a3484
pdf-font-stream PDF embedded font (sfnt) at offset 0xC883 15796 bytes
font_02_sfnt_off0000f0e4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E4 16792 bytes