Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8154c54be0bf00b…

MALICIOUS

PDF

84.4 KB Created: 2021-09-07 09:37:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 38a827a056797f08a310cc1ee4a86eb5 SHA-1: 1a7f85945d3ba10740f9fc84fc3a766c307476b5 SHA-256: a8154c54be0bf00b30ee26b9e8aea065b6073efe5efffc8a98ea53c15f58138f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://infrive.ru/uplcv?utm_term=story+elements+pdf PDF link annotation
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608b9d863f53c---27274166605.pdfIn PDF document text
    • https://habibitours.net/ckfinder/userfiles/files/95606248879.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16075d9aa1bc99---goxoxowexexovurep.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/t79oloeo5l1audjjg27go6cqc5/84079496413.pdfIn PDF document text
    • http://askort.pl/Upload/file/75227086091.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/zidif.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/96908076749.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/tomabujov.pdfIn PDF document text
    • http://kidneytracker.com/ckfinder/userfiles/files/kevagodogugikunow.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16084382c0a4ce---83613474251.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/9214680309.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/58780327451.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16105c6a7a441b---93196794310.pdfIn PDF document text
    • https://nusantarabet4d1.com/contents//files/reperasekoxolagasadoguf.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/12499832496.pdfIn PDF document text
    • https://irisapp.cn/uploadfiles/fckeditor/20210625/file/16245573594847.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e76262dd4af---nuwamadujizedo.pdfIn PDF document text
    • http://cuacongtrinh.vn/upload/files/26635356403.pdfIn PDF document text
    • https://benmoonpharma.com/userfiles/file/55394971054.pdfIn PDF document text
    • http://fotofolliasanlazzaro.it/userfiles/files/xinodorufavufagudonu.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/39067839450.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/lewarirum.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/jivimuxogug.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/86847232146.pdfIn PDF document text
    • 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_off0000e46f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE46F 18328 bytes
SHA-256: b65e71008a3a20b266186950d935b9f3f3760de591c36f12b40d5d0a4382b0de
font_01_sfnt_off000113e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113E2 10592 bytes
SHA-256: cf874baa174b47d528ab9303875650f331fcef4244ee620cc807817811e405f9
font_02_sfnt_off00012c14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C14 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1