Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f8eca3d3d1c7ed9…

MALICIOUS

PDF

76.7 KB Created: 2021-10-05 10:04:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: a2dae42540bbc80a9ca4263ab757bcc0 SHA-1: 750aa97867ad7054287e54dd049a99f42f69571d SHA-256: 0f8eca3d3d1c7ed9ce6a905f76794441b595ec0c46f78e8574453a33a5eb5101
126 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it functions as a link farm. Multiple external URLs are embedded, suggesting an attempt to redirect users to malicious sites for phishing or malware delivery. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically points to a link farm on disposable hosting, reinforcing the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://zeguvietnam.com/uploads/ckfinder/files/bebezilobidozow.pdf In PDF document text
    • https://mallarpurnaisuva.org/go/file/33108515806.pdfIn PDF document text
    • https://pediatricpotentialsnj.com/PP/PPpng/files/gokag.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/budedo.pdfIn PDF document text
    • http://www.examnotice.in/uploads/files/83309761768.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/saniwime.pdfIn PDF document text
    • http://nbnjl.com/userfiles/files/dolixuzagokavuju.pdfIn PDF document text
    • https://superlitefan.com/uploads/files/gozonuxozimotugokutewo.pdfIn PDF document text
    • https://ms01bet.net/contents/files/99532701675.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/62626851141.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/fb72e5c0d4ed48abfad72877f6b8af5e/bagoj.pdfIn PDF document text
    • https://dzido.pl/userfiles/file/sobujijeda.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/94135147615.pdfIn PDF document text
    • http://clinicaveterinariabilancino.it/userfiles/files/90296564552.pdfIn PDF document text
    • https://svltv.in/userfiles/files/12614317353.pdfIn PDF document text
    • http://geose.ru/userfiles/file/52938919414.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/kumujolo.pdfIn PDF document text
    • http://marketypik.pl/zdjecia/fck/file/mujotikikutifurize.pdfIn PDF document text
    • http://gzcil.com/uploadfile/files/66614124160.pdfIn PDF document text
    • http://tokyoracing.hu/userfiles/file/feninezadilizanexisa.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/50ebc3c60f010a936e4de48ead265bf3/85810092664.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/45774019458.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=i+am+thankful+for+all+the+blessings+in+my+lifePDF 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_off0000c4b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4B6 18048 bytes
SHA-256: 49ea6a2a9ad8250f4ed0a4b1a4b197c3b377d29b86ecb8c72bf4d29cd8efb667
font_01_sfnt_off0000f37e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF37E 11060 bytes
SHA-256: 80f1d2ebfe03415e612c2f552417060811de953035681ed6a37deeac058fc5dc
font_02_sfnt_off00010d10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1