Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfad87539cb45f96…

MALICIOUS

PDF

78.8 KB Created: 2021-09-11 14:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 14785832e634cb071635083637e300e3 SHA-1: 8ce87d1cff5a9aa0555853ccacd1bc4b42ccb861 SHA-256: cfad87539cb45f96e2ec48e76c9149e26f0ab7a28d870bc755d463104ea101d1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous external URIs pointing to various domains, indicating it functions as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically identifies this behavior, suggesting the document is designed to redirect users to potentially harmful content. No scripts were extracted, but the overall structure and URL distribution strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 https://coretry.ru/uplcv?utm_term=naruto+live+wallpaper+for+pc PDF link annotation
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0f5278f878ce10035ef96503956dbf3f/70924979658.pdfIn PDF document text
    • https://prettygreekvillas.com/admin/fckeditor/editor/filemanager/connectofile/diwodosamivuben.pdfIn PDF document text
    • https://stephankeppel.com/userfiles/file/91714778366.pdfIn PDF document text
    • http://ktcz.eu/files/files/xuxojavajeko.pdfIn PDF document text
    • http://centronegozi.com/public/rumorunirejijerabosal.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210909_125141.pdfIn PDF document text
    • https://dm288.rs/slicice/file/lufokedajibakad.pdfIn PDF document text
    • https://adeptos.clevercloud.pt/images/items/files/47766030654.pdfIn PDF document text
    • http://danchrisjewelry.com/userfiles/file/82828424219.pdfIn PDF document text
    • https://gangnampools.com/contents/files/4758582033.pdfIn PDF document text
    • http://wrtour.com/FileData/ckfinder/files/20210901_01C6AF28E60EFBB1.pdfIn PDF document text
    • http://hvezda-pardubice.cz/files/file/wureteja.pdfIn PDF document text
    • https://austarpharma.com/upload/files/78042841018.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/vapodurogetobewu.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/c3ba798256e4f55e7fc78c4ca634b15d/xiwibejixubuwa.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/mijakofob.pdfIn PDF document text
    • http://domuran.pl/files/file/48411493370.pdfIn PDF document text
    • http://thuexe7cho.vn/upload/files/vekofefizilej.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/161301d1f769b1---49509920797.pdfIn PDF document text
    • http://thenext.pk/userfiles/files/16396850037.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/8263936438.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/75747908866.pdfIn PDF document text
    • http://emachn.com/data/attachment/file/dubezokejebon.pdfIn PDF document text
    • http://poltinka.ru/userfiles/file/xerosimazikarekikigiwoso.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/31754567582.pdfIn PDF document text
    • http://tiszaikaland.hu/upload/file/68648554364.pdfIn PDF document text
    • http://edallyshop.com/upload/files/guwalolusula.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_off0000ce33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE33 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e64a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE64A 10432 bytes
SHA-256: 53e5de35e64baac8468d6fc495fc9925d581fe43ef75db0ccc577a4277ae9881
font_02_sfnt_off0000fe1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE1F 18000 bytes
SHA-256: 2ab7b8feefd295c1a79a8c847303ed60561cd2bc1171b41656478a2ad19eef30