Malicious PDF — malware analysis report

Static analysis result for SHA-256 9437c1a224344caf…

MALICIOUS

PDF

85.1 KB Created: 2021-07-06 19:32:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: b35e4e43028716427606553a9cbd0958 SHA-1: c70cec1bfea64e2321bdee847fe294674cefb2d4 SHA-256: 9437c1a224344cafb13a0d38c180166f074e005b4e2fdd632b2b94793b43cc71
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it's designed to lead users to malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent. The file's structure and link farm behavior align with techniques used to distribute malware or facilitate phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/0nbomms3h82450gca8vqjku3v3/dususebopijozefenatagip.pdf In PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bd8d137b9bf---89132565136.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf743ea997---xefawisoxilodefaxo.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/86e15880591e038137be7fe5e4f9683d/sefelujexotu.pdfIn PDF document text
    • https://pima-alarms.net/slicice/file/fitikip.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/pizop.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/ujfkfjvk65m747pr21qg4drs45/89004758695.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/32431619730.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/mbj0mnhu40g61lp5cei1bnvqo6/30465790341.pdfIn PDF document text
    • http://skincarebylaura.com/clients/862251/File/tazowotilunudalasesepefuv.pdfIn PDF document text
    • https://egca.fr/userfiles/file/wavoroxikudawumov.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b46fc2dec---1036347999.pdfIn PDF document text
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/109974ab0abfe48ded85444ab19c5aa6/92878897.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/60585276105.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/nobimarujutivux.pdfIn PDF document text
    • http://ombs.ru/uploads/files/saludakobul.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160895906cb9ff---39064964858.pdfIn PDF document text
    • http://statewideroadservices.com/clients/879378/File/sutobijudab.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/cd27121114f49bb5b220f3ee9ede2305/wijibep.pdfIn PDF document text
    • http://styropapex.pl/userfiles/file/78676524795.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=witcher+3+magesPDF 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_off0000ec0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC0E 10572 bytes
SHA-256: 150e77aa6c216729cea78269a8b4d8611f5d438fa6d4d15197abce03206bd268
font_01_sfnt_off00010443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10443 16740 bytes
SHA-256: ece3aee3bce328460bd8c6cb4db07c9517c76f7cb328589a8a4c6167344692ca
font_02_sfnt_off00012fba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FBA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1