Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e73768ac4cf0507…

MALICIOUS

PDF

84.1 KB Created: 2021-08-26 12:19:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 270622812ce0697b2613c35c18d1d1e1 SHA-1: 7b6327de596557fae998790a7a8fbe4a60aebaf2 SHA-256: 4e73768ac4cf0507e87ce5373d787b841e4792c22d0dca8ec3b12de168e3fb59
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609101c65138d---gololorupekuxoj.pdf In PDF document text
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/4b7f8aecca9186a0a51652f4b49562d3/pevadogetikal.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/xokenev.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/pizet.pdfIn PDF document text
    • http://goreskyreunion.com/clients/b/ba/ba087d28c24afe6c5bc45fa062332e47/File/vozufaw.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/00fcb450da550949d2a6d88e6c8cbeb0/jujejowufaril.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b825425ab72---64228571205.pdfIn PDF document text
    • http://cityhigh78.com/clients/2/2d/2ddbae4fb74c169819b3574d76e4e264/File/66653967059.pdfIn PDF document text
    • http://caydinhlang.net/userfiles/image/file/junuwusid.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210729220932739479ugm01y2nbo2v.pdfIn PDF document text
    • http://soldresold.com/Shradhdha-Mehra/soldresold/final/ckeditorimage/files/kezagoxubu.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/4886954aca8286ce6a500ff0e2c9475f/dawimulelakojikafa.pdfIn PDF document text
    • http://lafiestadelmoto.cz/files/file/91589150001.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/9755698701.pdfIn PDF document text
    • http://www.diplomat2014.ru/ckfinder/userfiles/files/56745869310.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/do30jsj0qnvkvmkvslmi9qveek/16183509653.pdfIn PDF document text
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/39852740593.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/7t3pulptet4054bn5b8e319f62/98461523094.pdfIn PDF document text
    • http://kco.su/userfiles/file/nezerivuzukukapabipago.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/16100c9d58209b---6248919612.pdfIn PDF document text
    • http://stagelight.pl/userfiles/files/fatezarebijuzatisagi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=unintentional+weight+lossPDF 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_off0000e626.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE626 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE38 17008 bytes
SHA-256: fb8173012d471d6e45ae9685b3cbab53cf733e40ce46c82bb71d629854bdf612
font_02_sfnt_off00012ac1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AC1 10380 bytes
SHA-256: 917ae6e7667b0f73d674e1853adb1506633484a676fa365a2f0d840cdae980e9