Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1f98d71fdf95680…

MALICIOUS

PDF

81.0 KB Created: 2021-09-07 12:45:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fe683ddc7edb7865ecf87605b48324a8 SHA-1: 39d32eb9c315b05613b3cb1d53241c74b32bf853 SHA-256: b1f98d71fdf95680de739aa8deaafc57aa07c826d5c8738347c5d22f93bf1afc
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links pointing to compromised WordPress sites, suggesting an attempt to host and distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The primary attack vector appears to be a link farm designed to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 8

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160740c84a87bc---86872441805.pdf
    • https://bakwanudang.com/contents//files/bilifubavidanujurokopibi.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/7b260eppt6dlho4ieafd7a2hv4/defavorixilijobezoge.pdf
    • http://www.ville-civaux.fr/admin/js/ckfinder/userfiles/files/82220831627.pdf
    • http://artecgroupservices.com/imagenes/file/pexebepopubulavixaxuxu.pdf
    • http://wych123.com/upload/files/64460205126.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1609d054b6761a---gulitalufot.pdf
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ec4f5531e1a---tuniviz.pdf
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/9212710392206666a6d95709fe715f75/49431496144.pdf
    • https://samarpanbharat.org/trila/userfiles/file/70559543682.pdf
    • https://www.sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/49081873862.pdf
    • http://northmarking.com/userfiles/files/64715118684.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847b68b7f93---25887188184.pdf
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160748951206d9---42478366797.pdf
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/31thrgdc06l26pkh9afla6hd7i/boxog.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085bc54461aa---pefafipavosorafinakure.pdf
    • http://cukrarnakolbaba.eu/obrazky/files/luwiwid.pdf
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160987147a9aa0---pamurerup.pdf
    • http://goddesshair.net/upload/users/files/78373145427.pdf
    • https://coaching-jk-academic.com/ckfinder/userfiles/files/jadivuze.pdf
    • http://youandisagenix.com/ckfinder/userfiles/files/67037758365.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abf0888d957---65770850233.pdf
    • https://carlojans.com/cms/file/7026184220.pdf
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/6bfcafe405ada8992e8099840f1ded49/tubuwopuzet.pdf
    • http://johnmichaelharrisonlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gorojerogotekevifi.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=translate+german+pdf+into+english
    • 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_off0000d34d.bin
ce164166437ec9b6a2c826a8ed5df65a8e678238910d2fdc263967829123d73c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD34D 10908 bytes
font_01_sfnt_off0000ec16.bin
05d6aa753a09756be95546c05994fda52d1f8713f3f7c6a22158d1c825e34813
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC16 19124 bytes
font_02_sfnt_off00011e09.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E09 16792 bytes