Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bcf084e4b9343e4…

MALICIOUS

PDF

81.2 KB Created: 2021-06-26 19:31:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 37db085805627e7ea6c15151068c7820 SHA-1: eab576b73cc059c210b172654278d803dd63c95b SHA-256: 8bcf084e4b9343e44b84f5f7d759cb46e634130766c016093251ce75301d644a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites using the Super Forms plugin. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The link farm structure suggests an attempt to lure users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/0d26e2d106a513572d3666efd6ba1389/metesidikujokelesu.pdf In PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/ipbq4b529grg1kcokdvtqbi31e/pudadopulomos.pdfIn PDF document text
    • https://tranduongauto.com/app/webroot/files/images/pages/files/86437792289.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073fff8ace35---86847305024.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/00h5eea89ju8e1b46s4fit5nl4/75851242488.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160829e054f2ca---73891142414.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/bc1a40547266d03f4669cd1eaac541ef/debimepinuv.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/40157518862.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/mhr11ik6jmhj7cp48gk05lp1ps/11899414999.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4caf607508---jodedimerewotariwimotado.pdfIn PDF document text
    • https://tavio.ru/files/file/27919457181.pdfIn PDF document text
    • http://rainbowcaterers.in/userfiles/file/sufewixokubu.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/8a82266d47a3be347ce366f7e69503c0/nusewujovavajisuvato.pdfIn PDF document text
    • https://x-software.cz/data/file/66571887569.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085e0de8574a---faxikijedigoxase.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/gijibifojipawil.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/lepipipekub.pdfIn PDF document text
    • http://infinijewelry.com/userfiles/file/kajedagumozilokika.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/m7u1qlpdjv56hf9b550jdve0m4/sobikiwe.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc7e7a578e---82001766975.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/dcc2929c236a4603733bf9ddf58edddb/neravutekuziwejivuduk.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160aa896737b5f---56792270626.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/86136537216.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7ca338f5d---xatuwoviz.pdfIn PDF document text
    • http://firanywiktoria.pl/uploads/editor/file/rolenuzazavenatuvobofa.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160893d52a5c29---78617693409.pdfIn PDF document text
    • http://artospace.com/pics/file/80315067984.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=political+science+notesPDF 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_off0000da92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA92 17632 bytes
SHA-256: 33c6b659668da36439706ff47b17e48ea18303be8147b56d921ac1ec9a7ba01e
font_01_sfnt_off000108be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D5 10124 bytes
SHA-256: 2ff7c226bef7d01522725b140c4247a2cb3a03769c77f1b9a6f7da5597edef43