Malicious PDF — malware analysis report

Static analysis result for SHA-256 873bb6c1ea1ccc2c…

MALICIOUS

PDF

77.1 KB Created: 2021-06-29 09:10:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fb2686c6c8ebe53ecd9bc4b1b60ff5c1 SHA-1: c20769445faf4a61e6d20d9247be3bbe4fb6fded SHA-256: 873bb6c1ea1ccc2c28abdee3baf65545adaa4ac0cf24e96697cfc8a393f4dfdf
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous external URIs and link farms pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or redirection scheme. The document body is heavily obfuscated and does not provide clear textual content, but the heuristic firings strongly indicate a malicious intent to redirect users to external, potentially harmful, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • 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.
  • 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://queure.ru/uplcv?utm_term=knock+and+down
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608da7f4846a2---87251850177.pdf
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/ta4j36dlb0c0ucsdr9m4sfsiv0/14575256168.pdf
    • https://adasms.fr/userfiles/file/xowozuniremiw.pdf
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16077f1340a121---25938223540.pdf
    • http://php-lounge.de/userfiles/file/pajuzitewerutuwupokako.pdf
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/3oak3rci92hkcgv0hpe8jjhjfa/jejidafamadakisil.pdf
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608255f2dec68---dosovodox.pdf
    • https://festival.bg/fckeditorfiles/file/kejelefeboseperorax.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/623b95e9c82f1a115f9950f3bedacde7/saxugudupelaxelolisuxul.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/b5dd93a638f7c2288930cd2059dd84ce/bozesav.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a218822eca5---fasizaximavuvoguvirafuw.pdf
    • https://nadamasristorante.it/file/dimunazu.pdf
    • http://webbuilders.com/files/file/gilujefasewekasowuzuditut.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160b2cb39e27f6---jorinokupebo.pdf
    • http://www.alfapilates.pl/upload/file/lerotajuneronexe.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/0cbc5d5a5b0a538fcd91c703f00565a8/gazasur.pdf
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/28110570896.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c009b7a4743---2817653444.pdf
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/i3k64974bs9m8gmqqva4jt9q0d/wuvalobogimowuza.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16073f740dedbc---90163659228.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5e823c161---15692545163.pdf
    • http://www.bash.cl/media/file/59148875556.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a38c277635f---gumanagefonumufejore.pdf
    • 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_off0000c750.bin
2a5c10d5df1331624f9af35c3a9a49e209e384b88c12933da943c19defb88b92
pdf-font-stream PDF embedded font (sfnt) at offset 0xC750 19656 bytes
font_01_sfnt_off0000f98c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF98C 16792 bytes
font_02_sfnt_off000111a2.bin
55a373551b73b010949d1eaf5c2c0aa3a65737381ddb3eb3419eafab8fccc056
pdf-font-stream PDF embedded font (sfnt) at offset 0x111A2 9896 bytes