Malicious PDF — malware analysis report

Static analysis result for SHA-256 25679cafe9e3b98a…

MALICIOUS

PDF

84.3 KB Created: 2021-07-15 19:45:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7335896afab3cabdb7e68c311c898c3d SHA-1: 818144f395d52d3b9998523b9e56f86a5418e6db SHA-256: 25679cafe9e3b98a7b2272ec3d7427f6cc3f1469d1191a39bb0cda43a49c0ec0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links pointing to compromised WordPress upload directories and other disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload is being served through these links. No scripts were extracted, but the structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=motion+in+one+dimension+class+9+pdf
    • http://chelseacarpet.com/ckfinder/userfiles/uploads/xuparidulunodideseto.pdf
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/408876bb65aa5389d427f26f04b4c3a4/97875843599.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/07ce7eb2f3fdd0a387b3bed84e310062/xofaxurevafef.pdf
    • http://aarogyamedico.com/userfiles/file/lavube.pdf
    • http://acril.ru/ufiles/files/bejijojogonarer.pdf
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/64b60b77ce3b47bb7d481619c8bebf20/buvome.pdf
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/bsenn81q1ohe2sc49q51ik3be4/42474024768.pdf
    • http://faizleathergloves.com/userfiles/files/21862105198.pdf
    • https://istanbulbalbir.com/upload/ckfinder/files/43936611644.pdf
    • https://genimmigration.com/viking1/uploads/files/45815627182.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160baa99444493---13530429789.pdf
    • https://juvelyrikoscentras.lt/Files/file/gixoxijidikitotekudilig.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c15e555baa7---bulosanibemorosakafikur.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/129556e747ee718f208f07d5c37490cb/bamuxanusezulo.pdf
    • http://minutemen-jrotc.com/clients/84940/File/85602156233.pdf
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/f75736f6182787dfc1fa4bf0bdeb4176/lunusowutogulaworilubofox.pdf
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/hh45o4c20pqc8l9qq77k1fihb0/68861751723.pdf
    • http://wsm.hk/images/uploadfiles/file/viwekobugituzidateb.pdf
    • http://uforoi.com/app/webroot/uploads/files/sorazebejovirewefalokabik.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985c2406dd2---xopiv.pdf
    • http://lnaixi.com/userfiles/file/20210619102021_302569274.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_off0000e3b9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3B9 16792 bytes
font_01_sfnt_off0000fbd0.bin
f8efb76ca23882a5a33902dbcbc7ce63b2d524b8e542f3dc866af4a3415701fd
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD0 10840 bytes
font_02_sfnt_off000114d9.bin
e56e1ed5fbf7ac39d75608e7dd57a923fc9050fd649b9eb6d4dd28e1b30d8ab0
pdf-font-stream PDF embedded font (sfnt) at offset 0x114D9 17916 bytes