Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff5398bfa8f130b6…

MALICIOUS

PDF

79.7 KB Created: 2021-08-03 17:36:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c8ab7ad026f05239475a29338cc2e16a SHA-1: b6d71ff0f0f1c15536dfeca51f104a3e41ab7992 SHA-256: ff5398bfa8f130b62d42074a8d99ce09c48360b184593ac80d881e25ddeb6480
162 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or are part of a link farm hosted on disposable domains. The embedded JavaScript likely facilitates the redirection to these malicious sites, which are designed to host further malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6314

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.
  • 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
  • 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://laborke.ru/uplcv?utm_term=national+achievement+test+sample+pdf PDF link annotation
    • http://ajisushionline.com/uploads/files/33729929147.pdfIn PDF document text
    • http://yule-sign.com/upload/editor/file/20210728003126.pdfIn PDF document text
    • http://rotarylaspalmas.org/documentos/file/wutujojomuzubidu.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/5123c9ce19dada69276034457785e730/59206981062.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/0ff2df3685ab80eb17f203e3d6310754/ludifefikupinibusugotudez.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b115ad8a9---jesudi.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/ie6sbup8vfijk2ghovms293rh0/pigijudusitinuzi.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/file/fokavuxevolar.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab12661380b---gulukifib.pdfIn PDF document text
    • http://colorfulmedia.de/fotki/fotki/file/1416061155.pdfIn PDF document text
    • http://townsendrogersfamilyreunion.com/clients/9/91/912616e09393d205379ff76530a10a1f/File/jusezigovafan.pdfIn PDF document text
    • http://pazzo.jp/js/upload/files/30845830435.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/ba8e464018500260c45f779257cd4a4c/punizitijarijeg.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608461bf8e2d1---48248976608.pdfIn PDF document text
    • https://ms01bet.net/contents//files/93272887616.pdfIn PDF document text
    • http://gdbchurch.com/clients/43262/File/73974123133.pdfIn PDF document text
    • https://sitpchemcieszyn.pl/_sitpchem/file/55699378686.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/v07rod3pihtirffjf48snhq6rs/melirenob.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/89hj3qkna1sqb6rvk6g6s3m9q5/29133705854.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/xawitamobogasas.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/61356882811.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/p3f7fht58t4c4f5fnvluvke9a0/78199243793.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1b3dc135b---71440271154.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000102a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011abd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ABD 10828 bytes
SHA-256: 029e08cdaa16d1dcea5f00bc09f1c1efdb0c56bf01dd7f14a1530f46d489b9e2