Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac8e94279d7e24e6…

MALICIOUS

PDF

79.1 KB Created: 2021-09-06 22:47:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a39d2995b38614d556eff7f2bbf36f6b SHA-1: 85083de7f8c885585c5a0f00e53ed1ed9b1c2270 SHA-256: ac8e94279d7e24e6f8a8ce883f37e139c043d933ad08dfc5ff5c409c3881f72b
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 0.9953

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 http://aaaexpressheating.com/userfiles/file/60832077945.pdf In PDF document text
    • https://pharmawell.eu/ckfinder/userfiles/files/fezukopi.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d00f8ec33ed---kesizimudezezireban.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/16082a7ab61d50---sinedeperapitajibugaw.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16100ad14b2aef---vanifipegaluwori.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/63246116015.pdfIn PDF document text
    • http://bsa.by/ckfinder/userfiles/files/43144616238.pdfIn PDF document text
    • https://www.sterlingsez.com/ckfinder/userfiles/files/12181894649.pdfIn PDF document text
    • http://cobmedia.hu/include/wovig.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/8339620672.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1611f3f6ef0cb8---80428694664.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/gotoxurisebedofiseg.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/61898507299.pdfIn PDF document text
    • http://marta-galan.com/files/varios/file/28304876537.pdfIn PDF document text
    • http://banphimchuot.com/userfiles/file/2771491413.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/76ee712746ee9d5777e798c1524cd35d/84978421555.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/160a0acafe4a8b---xivini.pdfIn PDF document text
    • http://valsadindustries.com/userfiles/file/39495548902.pdfIn PDF document text
    • http://rauvuonsach.com/images/uploads/files/46856127069.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbb9959e6d---berisavalibunesavuxak.pdfIn PDF document text
    • http://maynenkhiinverter.com/media/ftp/file/60951789343.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/ed06816fa6bfdda52d56eca671b04d94/3496605675.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/13313752295.pdfIn PDF document text
    • http://nhs1980alumni.com/clients/878257/File/fogujizirotijifem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=voice+grammar+pdf+downloadPDF 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_off0000ce8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE8D 18480 bytes
SHA-256: e0f9e6a23faa40435f7e807a3b8aee8d2b2d2a322e949f348a3c6b6e58b798ec
font_01_sfnt_off0000fe7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE7C 10752 bytes
SHA-256: 496fbc4705f93c5d2f06ef3a9aa7df3ea411f555afd01b7a3e1f83686f088ce7
font_02_sfnt_off00011707.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11707 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1