Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8d10c287b112050…

MALICIOUS

PDF

85.6 KB Created: 2021-07-05 16:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 0b45e350da3d3c21a2a20b87ebb2695a SHA-1: 3e68dc6e9d536f078e011f0e7bfe5cc1b337fc85 SHA-256: d8d10c287b112050bd8954b99da583ed199ab9e766f98bfcb4e28a3d6f9593e6
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised WordPress sites, with numerous URLs pointing to PDF files. The document body is unreadable, but the structure and URL patterns suggest it's designed to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b14b8fabe9a---buladezigogavezawivuf.pdf In PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/777ea23cec76e7ff860aae39429b1254/kiremazuzovuwepos.pdfIn PDF document text
    • https://idd.no/ckfinder/userfiles/files/3511530533.pdfIn PDF document text
    • http://urduhadith.org/survey/userfiles/files/tibakejajujadugis.pdfIn PDF document text
    • http://buergerforum-tirol.at/file/14407999639.pdfIn PDF document text
    • http://orvosvalaszto.hu/uploads/files/tapinetajiwowofasubo.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/12622054690.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/nunej.pdfIn PDF document text
    • http://www.minaakshimajumdar.com/fckimages/file/lamofesa.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/qp5g271i2q527g2kgogsh55ja4/68516198547.pdfIn PDF document text
    • http://chinahongji.com/d/files/dixofumudaxikamoruzomelu.pdfIn PDF document text
    • http://chiangmai-esc.net/user_img/files/75336217853.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/f62234bc989e7944e0898c9d0aa27dcb/1540358550.pdfIn PDF document text
    • https://bataretak.com/img/files/file/94269232464.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/bavuka.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc6e3a1369d---5922497024.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d155831d07---62261420327.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/20236979971.pdfIn PDF document text
    • http://yomamasushitogo.com/uploads/files/89465560500.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160821d2d47761---duwigofeliz.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d3c59cd16---42328227257.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/tejapejexibevumigu.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/vobanu.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/15867321260.pdfIn PDF document text
    • https://travelsafeway.com/userfiles/file/nilunupedoxam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=cucl+compound+namePDF 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_off0000ed9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9F 16984 bytes
SHA-256: 639266a0211c187791b5a0342ca5049eea13f37c008c1176179cbe355a36b9a4
font_01_sfnt_off000119f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119F9 10348 bytes
SHA-256: 5600e17a9aff68436e003ab150c0b922b63732fb8fe53223fda6586d9a5506ca
font_02_sfnt_off0001314b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1314B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1