Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8f762b0f265c3b9…

MALICIOUS

PDF

114.5 KB Created: 2021-09-06 12:19:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 576845632c7e05178997f470a4da886c SHA-1: f3410b4caf263b5f58cd2759db06b3f48dbdd2a5 SHA-256: e8f762b0f265c3b93200008991d687ae0efecb5b4fbedc53f05ba98d1acc2d6a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, containing numerous embedded URLs pointing to compromised websites, likely to lure users into visiting malicious content or downloading further payloads. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://pistant.ru/uplcv?utm_term=gcse+transport+in+plants+worksheet PDF link annotation
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609264855afe6---29763496247.pdfIn PDF document text
    • https://ceramicasvillaflor.cl/UserFiles/File/vowodikebe.pdfIn PDF document text
    • http://pettwayfamilyreunion.com/clients/39389/File/xuposutusepiraboz.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/ac2583iomg03mc2qi38t5ncgv7/sowib.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/a696f88015c069f2ed1824a9ed766efe/zekezifu.pdfIn PDF document text
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/d45951bfc92c23b826215b80c21609aa/lemesozozawot.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/gelidizabifutaxob.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160da9677a96f6---65081663179.pdfIn PDF document text
    • https://procogs.com/FCKeditor/file/88932482087.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/44435330630.pdfIn PDF document text
    • http://clinicaveterinariasangiacomo.it/userfiles/files/23339694987.pdfIn PDF document text
    • http://recit-de-vie.fr/userfiles/file/gosojenopiru.pdfIn PDF document text
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/sibuj.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16105a4fe1868e---wijukifixitimurem.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a781a979489---51279482243.pdfIn PDF document text
    • http://geosond.pl/userfiles/file/33974868733.pdfIn PDF document text
    • http://thesecurityguardunion.ca/userfiles/files/talozigakexofusif.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/10i5bl3s1v2fhvbla877p21853/sekorewebojidujesunus.pdfIn PDF document text
    • 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_off00015a01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A01 10688 bytes
SHA-256: 4c9db4c6b82813ba8a7d00b36e0c573ec57cd57635e2546f3b9aae1a89293509
font_01_sfnt_off00017286.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17286 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00018a98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18A98 19176 bytes
SHA-256: 338f44efa92c9fe99eef17a4ef931471d00426f8c7859f6addfd621970e27493