Malicious PDF — malware analysis report

Static analysis result for SHA-256 18524e32e9f84052…

MALICIOUS

PDF

79.8 KB Created: 2021-07-02 08:16:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 33df970bcf836ae8b353fbee283f8ecf SHA-1: c042b0016faa0d1d287e5549adf50e3fa4dcc622 SHA-256: 18524e32e9f840524fccec168bead7c21651350b0ad66fbf0a99da4003b14cdb
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery via these links. The file's structure and URL patterns align with common tactics for distributing second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://chcial.ru/uplcv?utm_term=harry+potter+pictures+to+colour+in
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/28048354075.pdf
    • http://wallsfamilyreunion.com/clients/876683/File/segelumumidudopofonatini.pdf
    • http://qytbearing.com/upfile/file/pewizogifaruzokavujibo.pdf
    • http://ankamet.com/userfiles/file/merutotilukaxabujureniku.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160811eb815036---77407527003.pdf
    • http://princeverma.in/uploads/files/wapazafesebupesiwugub.pdf
    • http://firmykominkowe.pl/Obrazki/edytor/file/23038266257.pdf
    • http://agiusfuneraldirectors.com/files/file/beresininulisawodigubu.pdf
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/6dc5d05fb024cabcf25ea0abb51d3c49/87125165015.pdf
    • http://boekenwinkelindex.nl/images/uploads/dedazozeretefo.pdf
    • http://ural-kip.ru/admin/ckfinder/userfiles/files/78124648592.pdf
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/u149h437j09onm6canant9tsv6/sevitaworujelow.pdf
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/q6vankahjicgme56ju5sje65lj/45569906637.pdf
    • https://777mto.com/contents//files/deseri.pdf
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/hnj21phgvgo9rqhb5stlfuluku/senituvuf.pdf
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1609dcdbb2eea0---dafutilibazafa.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088f8759d9db---9828174214.pdf
    • http://pusancard.com/userData/board/file/41091940069.pdf
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/aeebb8494493df8cddf2548eae37232e/jofiwaxewiperejezojut.pdf
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/tp9rkj6oodborl0r4sis1qic8c/41607485845.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/fda40bf47f05ace651acf5c41fe67044/lenaguposozazoru.pdf
    • http://www.microsinusectomi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160773c4ac7827---34979115668.pdf
    • https://lawina-radom.pl/files/file/1796771131.pdf
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/usqktfoia5j3brtq2rdht4jrub/84855057625.pdf
    • http://utuin.net/files/fckeditor/file/dakuxus.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/3f54a5c229fe422e75d94e51908f7a8a/budukadubite.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_off0000d56d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD56D 16792 bytes
font_01_sfnt_off0000ed7f.bin
9d79f654ece8a30b77777b1235d72a91a9ce22d8b4222f7e410949716664941d
pdf-font-stream PDF embedded font (sfnt) at offset 0xED7F 16872 bytes
font_02_sfnt_off00011941.bin
b500e887d88b6770d714ae792a29e31015bfa2d4c6359c98b3d814448622cff1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11941 10572 bytes