Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ee7d558ad18b0de…

MALICIOUS

PDF

72.6 KB Created: 2021-09-28 03:05:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9bda1ef4b8a8de8512a043bf0cced041 SHA-1: 826db53b7fef743046045d002c85482da4ac7484 SHA-256: 5ee7d558ad18b0de9701d904462f1f14e987df0c9d22fb50ec876f6ef3daab73
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm on disposable hosting, with multiple URLs pointing to PDF files, suggesting a phishing or malware distribution attempt. The document body is heavily obfuscated and contains no readable text, further supporting the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://rheumatology.institute/upload/content/file/wuwulazafiwonamu.pdf In PDF document text
    • https://035620126.tw/upload/greenkitchen/files/rorumuxoguve.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/menorozuruxanudiruwu.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16147168e8d499---44433758571.pdfIn PDF document text
    • https://brawlcall.com/ckfinder/userfiles/files/32879482738.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/161403202e1b09---fuduxobetozepirakunurobu.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/161525317eba00---54885800112.pdfIn PDF document text
    • https://fotoprint.lv/downloads/file/galonazunawezuburadumofu.pdfIn PDF document text
    • https://gujaratisamajparis.org/upload/files/golemituvagejawelapa.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/mosalutizediw.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/34700306587.pdfIn PDF document text
    • http://indianspringhomes.net/userfiles/files/fekanawoxopuripibexepufo.pdfIn PDF document text
    • http://asorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/59046365083.pdfIn PDF document text
    • http://thucancakoihikari.com/luutru/files/nozojabix.pdfIn PDF document text
    • https://arabadvertise.com/userfiles/files/72882851125.pdfIn PDF document text
    • https://rajaunited.com/contents/files/16746626645.pdfIn PDF document text
    • https://www.frontiermea.com/sites/all/libraries/ckfinder/userfiles/files/97000009710.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/43155169037.pdfIn PDF document text
    • http://hakasasi.id/userfiles/file/1236294055.pdfIn PDF document text
    • https://kohphanganhotelandtour.com/userfiles/file/34120098148.pdfIn PDF document text
    • http://dezmaster.com/userfiles/file/54662513436.pdfIn PDF document text
    • http://artepcb.com/upload/files/wopewisuso.pdfIn PDF document text
    • https://academiapreprod.riportico.com/userfiles/files/85012261713.pdfIn PDF document text
    • http://www.hausman.eu/images/wyswig_images/file/25735627603.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/99977849214.pdfIn PDF document text
    • http://conhantaoankhanh.com/webroot/img/files/32539472931.pdfIn PDF document text
    • https://lapalettedesarts.fr/gestion/file/30768043470.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=master+vpn+lite+apkPDF 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_off0000b74b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB74B 10276 bytes
SHA-256: 0710a7b019215788bea9993c6f4aa2832e26c898dc91b9c21686b736c8e93e16
font_01_sfnt_off0000ce88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE88 18052 bytes
SHA-256: f5752925e2bc1c26e93a6e76b0a4d320821ec336b1e0df27508e674fa4985fde
font_02_sfnt_off0000fca7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1