Malicious PDF — malware analysis report

Static analysis result for SHA-256 def6977f5bc8fd15…

MALICIOUS

PDF

85.7 KB Created: 2021-09-17 15:15:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 13c62eb8936c7ce345dd394c4bb060aa SHA-1: 5a9f428d522728a7496e6adf787c13259cba8c9d SHA-256: def6977f5bc8fd15a1ceda9bb6c9a251a0c79debb8312a2428414393680c1692
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of embedded JavaScript points towards potential exploitation or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://cructi.ru/uplcv?utm_term=aplicaciones+para+girar+la+pantalla+android PDF link annotation
    • http://littlepearlbooks.in/data/eimages/file/32551268709.pdfIn PDF document text
    • http://tornyanggrace.com/upload/file/50579291789.pdfIn PDF document text
    • http://myucmas.com/userfiles/file/62365761906.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/velizasikoz.pdfIn PDF document text
    • http://www.park-seversk.ru/other/js/ckfinder/userfiles/files/sesakatosenukenevirarebo.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/vereduxafelebakojex.pdfIn PDF document text
    • https://begili.com/uploads/image/files/57972851552.pdfIn PDF document text
    • https://vanrun-it.nl/userfiles/files/25282521292.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/64895715626.pdfIn PDF document text
    • https://tunhuaduytan.com/upload/userfiles/files/6138651916.pdfIn PDF document text
    • http://33podarka.ru/pictures/files/25394704147.pdfIn PDF document text
    • http://old.arcnet.org.tw/ckfinder/userfiles/files/sefarimimaxaxuteb.pdfIn PDF document text
    • http://gkz-crimea.ru/userfiles/file/wunodukokedijikafisimef.pdfIn PDF document text
    • http://studiodugnani.it/userfiles/files/77290307381.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/l6n99bbmn6jlrb5csmoi7osj0m/55661917658.pdfIn PDF document text
    • http://aptwash.com/userData/ebizro_board/file/forisevuripibokakeso.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613870559cdc6---nomisitezuzog.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/16135276f6f77e---93208114366.pdfIn PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/tosotanodeg.pdfIn PDF document text
    • http://zhodnoceni-penez.cz/is/images/FCKeditor/File/vufakuxulosomuzasexam.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_off0000e5d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEB 10672 bytes
SHA-256: 8c19ceed2ad5cd8bcf02d707dc4a0214631c572a1a6efaece7d1f82ce939648f
font_02_sfnt_off00011656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11656 19560 bytes
SHA-256: 868c4fa20e7a200b278e8a53535a0193469d8383b4a98fe38b98abd7f32bc996