Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf723173b0990811…

MALICIOUS

PDF

82.4 KB Created: 2021-09-06 02:06:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1b2a0e462ce76435caa9aeb41608fabe SHA-1: 29fc349e3a9cc1f811911fe83891e1e63ffa02ea SHA-256: cf723173b09908111ac6d87a388ec78f9ac9eab94939a5f3a01bfdd226fe9882
164 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous external URIs, several of which point to compromised WordPress upload storage. The ML classifier strongly flagged this PDF as malicious, and ClamAV detected it as a phishing trojan. The presence of embedded URLs and the nature of the link farm suggest an attempt to lure users to malicious sites, likely for phishing or further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://doellefjelde-mussemarked.dk/images/newsmail/file/ginuzatejexefud.pdf In PDF document text
    • https://armagedonspedycja.pl/files/file/1026713011.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/0527141065864d8ec53921bfa9add334/37079949193.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/74169017554.pdfIn PDF document text
    • http://bayzones.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/wogobu.pdfIn PDF document text
    • http://status.cz/UserFiles/File/86641702503.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7ce24ea02---nenuv.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/vudofijivoxetabobofun.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/wisazofebis.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/26481876639.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/e24de5733cd84e8e586c2afe16be3475/50201281165.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/jubodelakorimafa.pdfIn PDF document text
    • http://axwelindia.com/uploads/bobudagegir.pdfIn PDF document text
    • http://bsinteriordesigner.com/userfiles/files/16656241330.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/tigigelulelowinanofopa.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160cd032856b5a---21580090988.pdfIn PDF document text
    • https://cafesca.org/ckfinder/userfiles/files/14893945937.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/61061028482.pdfIn PDF document text
    • http://angelsolutions.ro/ckeditor/ckfinder/userfiles/files/28580974726.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b2fcab755bd---13002861107.pdfIn PDF document text
    • http://envida-nieuws.nl/bsb_website/upload_fck/file/43477777798.pdfIn PDF document text
    • https://grup-insaat.com/userfiles/file/getaxomivonasexuli.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16095f002f03e5---3139560706.pdfIn PDF document text
    • https://o-dance.com/upload/files/gukas.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/0b21f492a63878e264e4be5fb942842b/81799350558.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=coding+and+decoding+questions+and+answers+pdf+for+bank+poPDF 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_off0000dae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE0 11344 bytes
SHA-256: 5ac79868675ebcded2d88fb0474a22894f7acf1e1c1197708c5a656743c8a1fa
font_01_sfnt_off0000f50c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50C 17664 bytes
SHA-256: b9cefcaa7c26eeecc323de17ad661a9e957a94120fa6beb2067fa9e52f8164b8
font_02_sfnt_off00012307.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12307 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1