Malicious PDF — malware analysis report

Static analysis result for SHA-256 53786fed4da467ac…

MALICIOUS

PDF

84.0 KB Created: 2021-06-26 09:20:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8e8cd210466aef718a4f81e0158ac761 SHA-1: 6e9b311c9c432a0fce1b9dbc52cda7ef2d82541e SHA-256: 53786fed4da467ac9905ca70f43650a9b4d846393a86ab64716d17e7326ebee2
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 compromised WordPress sites, suggesting an attempt to distribute further malicious content or conduct phishing. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/q7p70lin9aec4a7uoh7ufbef61/88230605898.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/inupau1552lrd8c0gqpqgbbo15/30458189843.pdf
    • http://robalton.es/Albums/images/file///15985275427.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be18555e035---wopakawamejek.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/8k92sg3c6u72ma9jein16p674u/30955358526.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071b3c8e9b06---gapaxigejotavo.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc1ae08cc3c---larozodivenibaxaj.pdf
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/73gsd0d4i7kpva30lu7n8blhjh/wazejaxudavunadub.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3266c1f18e---8175888200.pdf
    • http://bobiniauto.com/userfiles/file/74483326929.pdf
    • http://bigsvatcharasith.com/userfiles/file/kemomejasavef.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea831b6783---dogugemenimav.pdf
    • https://masihpt1.com/contents//files/buzozenoralo.pdf
    • http://angelojrobles.com/admin_initial_test/userfiles/file/gubenibiniliwajebusato.pdf
    • https://noble-program.site/js/ckfinder/userfiles/files/28238912834.pdf
    • http://mosjob.ru/images/file/5737443296.pdf
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9de2a089d---7401584265.pdf
    • http://bagiez.com/userfiles/file/zigob.pdf
    • https://parklanehotel.asia/userfiles/file/20819677305.pdf
    • http://mu-rrrc.com/userfiles/file/96858169163.pdf
    • http://mtsskzy.com/userfiles/file/tixikedonoravipu.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160703c6fd2e30---30735065578.pdf
    • https://fanaf.comarticle_ressources/file/wufuk.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=summary+of+thank+you+mam
    • 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_off0000e688.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE688 16792 bytes
font_01_sfnt_off0000fe9f.bin
a7639ef3085ada76d5ffd3bb76f66d44734787fec387cb3fbf24b8b754982f01
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE9F 10424 bytes
font_02_sfnt_off00011617.bin
0492b511e1516dfd4615d76fc7f1540c03991f96067e7f35da6e754042316b87
pdf-font-stream PDF embedded font (sfnt) at offset 0x11617 16792 bytes