Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5f19628e307f7b2…

MALICIOUS

PDF

81.9 KB Created: 2021-09-08 12:10:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-24
MD5: b82ac2a30070e3ec54355ecf4217defb SHA-1: 9376819295ac725671d8abd8fb7e8aa5dd0ff4fe SHA-256: d5f19628e307f7b24f253237308fe72248507f1edc405639ac2080e81bd44d89
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 0.9957

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://amirep.com/wp-content/plugins/super-forms/uploads/php/files/339ca4e488baafeba740d063ab58f857/18817461804.pdf In PDF document text
    • http://madveras.com/ckfinder/userfiles/files/piduneba.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a3633e6790c---nawowogitimine.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16098ad6408662---26366038738.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/8ffe80f0d28f7cc0a4dc063b1d2fdade/xebonifexukab.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/nububanewir.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16080ab0a539ed---27727288949.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afe660eecbf---3025651536.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/70e0febc803a5f88ce39015c4a38e276/sizuw.pdfIn PDF document text
    • http://tykhestudiodesigns.com/clients/7/73/7311521ca682816632878891c231d107/File/nukemuxivoximixuwuvikotiv.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/vasupezizakapev.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160c30b1dcd3b4---37020636436.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/331eab12ffb0d81fc8be9c4c64f255e0/34184244333.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/silukutofivanunidekipawes.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9290e824a2---37335364897.pdfIn PDF document text
    • https://armandofalconi.net/userfiles/file/60646872403.pdfIn PDF document text
    • http://yourhealthyanswer.com/ckfinder/userfiles/files/derezisu.pdfIn PDF document text
    • http://opalsolar.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607a4b0806330---29311244355.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1609df1925fe53---noxofizebewofukolaro.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/9e37bda0901850bc55b8a6ee372ea86f/mekukusetekumar.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/nejumanifatet.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/20522095309.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=connecticut+medicaid+provider+billing+manualPDF 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://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_off0000ddd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD9 18396 bytes
SHA-256: 876df8897f3707a74f1bbbecebb3f17839e7875887a38d9e6422beb4a9c6044d
font_01_sfnt_off00010d86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D86 11024 bytes
SHA-256: e453f34e2b4c4dc5f0543cf407fe72f3acabf514438d378ab1f6800689c34563
font_02_sfnt_off000126bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1