Malicious PDF — malware analysis report

Static analysis result for SHA-256 61f5d0f79715bfb3…

MALICIOUS

PDF

86.9 KB Created: 2021-09-13 04:07:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c976a138579a1948062c658615d6941f SHA-1: 15c0bf0259a9fe84a0e58f0ad3c1184f002121d0 SHA-256: 61f5d0f79715bfb33e00061a88f4124ee31d9c1d9fd2e60ec57707b24b4ccef1
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The sample is identified as malicious by ClamAV and an ML classifier, and it exhibits characteristics of a fake CAPTCHA lure. The document likely aims to deceive users into interacting with it, potentially leading to the execution of further malicious code or exploitation. While no scripts were directly extracted, the presence of numerous external URLs, some pointing to PDF files on potentially disposable hosting, suggests a downloader or phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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://basalyemek.com/ckfinder/userfiles/files/revuf.pdf In PDF document text
    • http://prochem.vn/images/uploads/files/xukibadelifexefidijof.pdfIn PDF document text
    • http://bannhuaduong.net/upload/files/fixujedizuzitoz.pdfIn PDF document text
    • http://artvideo74.ru/upfiles/files/virefukenopeko.pdfIn PDF document text
    • http://studiotecnicolamanna.com/userfiles/files/46505192672.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/wurer.pdfIn PDF document text
    • http://gabortech.com/admin/file/15804650313.pdfIn PDF document text
    • http://herborgthailand.com/file_media/file_image/file/kugezajagijoxubiva.pdfIn PDF document text
    • http://cbgnfinance.com/userfiles/file/sujoponarimun.pdfIn PDF document text
    • http://chapraptti.org/userfiles/file/dagiw.pdfIn PDF document text
    • https://braveathlete.net/geektic/files/bubolidutojufexiwimexa.pdfIn PDF document text
    • http://anninh247.info/upload/files/6746470833.pdfIn PDF document text
    • http://seowonbattery.com/files/fckeditor/file/1214081582613d82d70cfd8.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613de0051e4f2---pugewazisiz.pdfIn PDF document text
    • http://www.saaegfpolis.org.br/ckfinder/userfiles/files/kabenofo.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/daxizezezevila.pdfIn PDF document text
    • http://leeharringtonhomes.com/userfiles/file/52135111885.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/66211056595.pdfIn PDF document text
    • https://kompaspt2.com/contents/files/54383901302.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612efdbc7e9c4---wimuligipumadez.pdfIn PDF document text
    • https://mlspoland.co/files/file/14791865787.pdfIn PDF document text
    • http://12shio5.com/contents/files/geziragutejabeto.pdfIn PDF document text
    • http://epoxidice.ro/mm/file/38851314329.pdfIn PDF document text
    • http://qualityspices.in/ckuploads/files/59799205289.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=mac+m1+android+emulatorPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d53d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53D 17920 bytes
SHA-256: 170366c5b5c8fbaf77979d52f72fa2a759ae25528d3a98497f0f07ec3cc5a7e2
font_01_sfnt_off00010468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10468 17268 bytes
SHA-256: 7912c89ebbf54678e8f5c7c1d0220f297d90ac373931578dba8573c3e68b8b36
font_02_sfnt_off00011e01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00013618.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13618 10508 bytes
SHA-256: 2ce3de5c595c3415bbb7179a81a1a73830540b599e3f415eb78019c5d3639135