Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f81b48332f849a2…

MALICIOUS

PDF

90.4 KB Created: 2021-09-05 21:44:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 51c85f5af6c46650ae27f258411041ef SHA-1: 266e7c5cd893010140a7e0988983202320fda895 SHA-256: 5f81b48332f849a232365126e7a270b22c1f1a1557359667d349ed8c69e195a6
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple compromised WordPress sites and disposable domains, indicating a phishing or malware distribution attempt. ClamAV and ML classifiers flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting. The embedded URLs suggest the document's purpose is to lure users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/6b795ed7e28e4850358d788a38180165/xuvizegi.pdf In PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609f224bc7415---sawimumu.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160741c31a5c49---6840046765.pdfIn PDF document text
    • http://stepasidemedical.com/images/uploads/file/mulozunotupuwomo.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aab0b43f31e---fuwudef.pdfIn PDF document text
    • http://anvlaw.com/userfiles/file/forulerokeriwabe.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f270e027cf4---87005698541.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/jivixus.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/falanumitipebajideva.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/jibizudebudedofavuwireza.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///susopalizedesobafopisep.pdfIn PDF document text
    • https://beautydiction.com/ckfinder/userfiles/files/ronutinaxubovuvulutaxifi.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/86105860789.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16084851e84a38---32337050306.pdfIn PDF document text
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/65121084e3ad6ad71ed762b7b2fd3ebc/19327087230.pdfIn PDF document text
    • http://screen.by/images/file/zopodominejevelijigev.pdfIn PDF document text
    • http://smcertificationservices.com/userfiles/files/27410593713.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dcc931f15bf---mikad.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/16d299f10e6a44d2f8d8286b9bb3a886/punitokobitanawobuji.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/31041532385.pdfIn PDF document text
    • http://candientuvibra.com/images/file/17263150048.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d42b0dcfe63---zegafogen.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160c8a2ff8ad77---69136812700.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/33710594668.pdfIn PDF document text
    • http://cunningham-reunion.com/clients/7/73/7399477c88ef979e1ad3ac38e42cffcc/File/xupaxo.pdfIn PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/hse2ou435brjbg6sha11jl5072/maduma.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a703b7d7f5c---vubanijunabu.pdfIn PDF document text
    • https://fullmagicweekend.com/ckfinder/userfiles/files/sugaded.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=sears+300+series+water+softener+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://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_off0000fb8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB8E 17492 bytes
SHA-256: 1386669c51b1f3ea58c6e74f5300697a032abba8f56e541b9487bfb91344a667
font_01_sfnt_off000128a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000140bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140BB 10932 bytes
SHA-256: e3050efde8c69f050c11753b77fe2f986e0df38096f1c9b0e7c111001e3e78f4