Malicious PDF — malware analysis report

Static analysis result for SHA-256 16d44dba3cd5a7b2…

MALICIOUS

PDF

83.8 KB Created: 2021-09-20 09:29:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: edfd279d4fe46410315bc5ab85b11bfe SHA-1: b0add186feff50d113c671a64bea4c495682ec64 SHA-256: 16d44dba3cd5a7b2c6243bf8ddd9ab9fb0c3b26dbff5ea613e060a83ca2ba051
164 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute malicious content. The presence of a 'download' button lure further supports the phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/9sbf2ukuovp0tkm4ege00pkrf6/gekubu.pdf In PDF document text
    • http://koslita.eu/ckfinder/userfiles/files/nuxejitureletopaxelibib.pdfIn PDF document text
    • https://jimsdelibrookhaven.com/demo/jimsdeli/admin/userfilesfile/wamegafonixoxof.pdfIn PDF document text
    • http://ituor.ir/basefile/chartermeinfo/files/kutilisanidi.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/91626273996.pdfIn PDF document text
    • http://color-gateway.com/userfiles/file/73951148254.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/342e2bcf08fd046bc2dd5ff99d670827/96135260144.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612efaa2bf30f---bovusofazololel.pdfIn PDF document text
    • http://saktigroup.in/uploads/14922089772.pdfIn PDF document text
    • http://plise.org/userfiles/file/26670048861.pdfIn PDF document text
    • https://ichapps.com/ichapps/ckeditor-ckfinder-integration/uploads/files/39706493237.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/qgmmb519llchk3lg2g54folngr/35113009410.pdfIn PDF document text
    • http://marinaxaraes.com.br/ckfinder/userfiles/files/59827994902.pdfIn PDF document text
    • http://vistobrasil.net/uploads/file/romojefibebuvulafi.pdfIn PDF document text
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/94923860673.pdfIn PDF document text
    • http://1careglobal.com/upload/files/jifuginojosi.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd5438dcec---61683539262.pdfIn PDF document text
    • http://maimungkorn.com/UserFiles/file/zavomadilunikuzekowimika.pdfIn PDF document text
    • https://norservis.cz/files/files/biwokasakatularamizewin.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/fixanixofepixubapizemomot.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/lavexujuwupim.pdfIn PDF document text
    • http://leasingtowers.com/ckfinder/userfiles/files/mekofixif.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161361c8be4912---71920603737.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=watch+dogs+mod+apkPDF 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_off0000e378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE378 17832 bytes
SHA-256: 9ab1986def6ed7c2754d9fbae9141cf28598c1af8cdb5792b58151fa403bf51a
font_01_sfnt_off000111ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000129c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129C4 10572 bytes
SHA-256: 32f3d27c7f998f23e036a0a12c69976e372a7e1be3fe6bb3bec10a22cf4fafec