Malicious PDF — malware analysis report

Static analysis result for SHA-256 55c46da65d570803…

MALICIOUS

PDF

71.5 KB Created: 2021-07-03 10:47:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e9f79f540dc7cc67488d5b968f75412d SHA-1: 239bd09af8ad0ba77a46ddb12585ed893b2a3b01 SHA-256: 55c46da65d570803d6ccecd66f336205812ed6ada91208396e0dfdf1563a2088
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites used for hosting PDF files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm designed to manipulate search engine results, and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' suggests these links are hosted on compromised content management systems. ClamAV detection and the ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • 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://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a65fc1c89bc---94834779291.pdf
    • https://almoheetmanpower.com/public_html/userfiles/file/55747794803.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/8283b323fb289315643440022c618faa/28673859865.pdf
    • http://anhbanglaw.com/userfiles/file/48943007707.pdf
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/0277371848f2c92ddf8a62aa63852239/kowamoxepu.pdf
    • http://www.anjhimayath.com/upload/file/4480022010.pdf
    • http://studio5r.com/userfiles/files/zapagutizu.pdf
    • https://iohrp.org/f_files/files/53179361492.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/652b55b8a4694c8a490d96d56169f878/norogaxoxer.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160ac900e5e039---fivojuvag.pdf
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/uit07apcp5mag2ffhgvh99dlug/sigosolute.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db3533c934d---tudamu.pdf
    • http://afgventuregroup.com/cfiles/file/83678884685.pdf
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac22eb6d593---568768201.pdf
    • http://kaowei.tw/image/files/20210616_092012.pdf
    • http://sonkertrail.org/clients/9/92/9260a3c387aed4615f72c72c3a1da295/File/70850727027.pdf
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/5ar5u22icrqtg5r8i1qvo4a5g6/59257744009.pdf
    • https://clumba-indoor.ru/files/files/dedewazifeloxurak.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/u7qqi65kjcc62qe5d17urvdf69/4233039891.pdf
    • http://446888.top/userfiles/file/66135642385.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078d1b3dae12---31389996315.pdf
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/a4n6vubnk1sqf624lig0sveeuk/31699890198.pdf
    • http://clinical-pain.com/pds/userfiles/files/rinubidagejijarewulegotaw.pdf
    • http://www.bandungmesin.com/file/ruxategonorozawo.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=confidence+interval+chi+square+test
    • 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_off0000b86c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB86C 16792 bytes
font_01_sfnt_off0000d07e.bin
9dc2df9ab6cb1846b2ec695006d5f93a086682cba07a276094fb5ec8b4395d72
pdf-font-stream PDF embedded font (sfnt) at offset 0xD07E 15248 bytes
font_02_sfnt_off0000f770.bin
3ed547adc49c794ac2bb0992a8ba730d96de7094933c76809e57867a411bb3e7
pdf-font-stream PDF embedded font (sfnt) at offset 0xF770 10916 bytes