Malicious PDF — malware analysis report

Static analysis result for SHA-256 5687121e8625abd7…

MALICIOUS

PDF

82.4 KB Created: 2021-09-18 16:54:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7b42643e04cb68568899f78b096c5d3d SHA-1: eb6263295f49b1649547f5c091dab10319d4f094 SHA-256: 5687121e8625abd7299e58db157482a5acf582914744368f73e19f24e7c37cc3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple domains, including one identified as compromised WordPress upload storage, suggesting an attempt to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • 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://www.confirmedtour.com/files/jiloxaditadonuxiwoxa.pdf In PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/27565581308.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134c7417abbf---88740941167.pdfIn PDF document text
    • http://to-kajihan.net/js/upload/files/tumeginijerozafotatova.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16136c0d033fb2---48862367529.pdfIn PDF document text
    • http://jornalespacoaberto.com/app/webroot/datafiles/editor/files/xutupoxasodetiwixojom.pdfIn PDF document text
    • http://leadingedgecorporate.com/user_images/file/pujiloputululajegofaxapen.pdfIn PDF document text
    • https://condicionamentofisico.com/arquivos/file/dibiwakajeli.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/ced3fdaed89525630b4db376aeeed0ed/xaxugitewibebifi.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/56736652057.pdfIn PDF document text
    • https://tierrettung-in-katalonien.org/ckfinder/userfiles/files/tipopa.pdfIn PDF document text
    • http://mintaialuminum.com/d/files/juvoforuwupatomabobi.pdfIn PDF document text
    • https://cvconstructionsgoa.com/pharma/admin/userfiles/file/senoladifagafibonezelin.pdfIn PDF document text
    • http://bangladeshceramicsociety.com/uploads/editor/files/bureminosupejewo.pdfIn PDF document text
    • https://www.natursany.com/ckfinder/userfiles/files/66371896766.pdfIn PDF document text
    • https://organicearthfiji.com/documents/file/91492681151.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/fe7439c28e609ab7454b7bfc5f87fdc9/30119944985.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/e666e46585f86181f496cc0ab137e6dd/larupibusowopokip.pdfIn PDF document text
    • http://remobudostol.pl/pliki/30128547307.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/dr70m0gi2f2rhqu6c63ngdq5fe/67270376797.pdfIn PDF document text
    • http://cutskytools.com/d/files/wefarakidogixeruxi.pdfIn PDF document text
    • http://geotersrl.it/file/labodobemaxusafavegelopo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=mx+player+series+download+freePDF link annotation
    • 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_off0000dbc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBC8 18176 bytes
SHA-256: 25827ffa98f262cd420de5380a99e516ae0f465d541b6533c14799139e4cf526
font_01_sfnt_off00010b2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12346 10688 bytes
SHA-256: 4f992cd8da032eb588574b94a891b1b8f54e2a6856ffc2ca92ce8386f174e7eb