Malicious PDF — malware analysis report

Static analysis result for SHA-256 57b5cefb822a1dbe…

MALICIOUS

PDF

80.9 KB Created: 2021-09-09 21:13:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fd3a9bece9bb416f16a86e82213385de SHA-1: 65fa149caac8bec208591a18c4e487dd4a8ecabf SHA-256: 57b5cefb822a1dbe57e9207096812596f2490d5bcfa33c9f09b02b7c164f56c5
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are flagged as part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware sites. The embedded JavaScript is likely responsible for initiating these redirects or further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://amgaa.org/temp/files/99023030284.pdf In PDF document text
    • https://vietnamairlinescorp.org/js/ckfinder/userfiles/files/lojoseliriwukabokagagex.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/gajcf5ght0uskgn93vahil4k99/xusivu.pdfIn PDF document text
    • https://heks-tech.com/app/webroot/userfiles/files/39474219768.pdfIn PDF document text
    • http://goksirlambinowice.pl/img/upload/files/92731049381.pdfIn PDF document text
    • http://52fotki.ru/ckfinder/userfiles/files/31060225171.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/161343ac0c7ff2---jivupezorijoworifazu.pdfIn PDF document text
    • http://spodne-pradlo-2bpoint.sk/UserFiles/File/tavozafuzevunoge.pdfIn PDF document text
    • https://kaptenhoki.net/contents/files/17903180829.pdfIn PDF document text
    • http://avs-market.ru/admin/ckfinder/userfiles/files/54059479082.pdfIn PDF document text
    • http://barefoot.pl/userfiles/file/42353467461.pdfIn PDF document text
    • http://szymonadamczyk.pl/uploads/fck/file/girefupidosuxewetapara.pdfIn PDF document text
    • https://bluza-shop.ru/content/File/rusex.pdfIn PDF document text
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jitevatafutere.pdfIn PDF document text
    • http://www.mousumibanerjee.com/fckimages/file/22864426865.pdfIn PDF document text
    • https://coolingrealestate.com/your-home-cleaner/FCKuploads/file/nulidimadetitesejixe.pdfIn PDF document text
    • https://dzido.pl/userfiles/file/gutaribo.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/80861141470.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/33248737166.pdfIn PDF document text
    • http://osmed.cz/app/webroot/files/files/82235799328.pdfIn PDF document text
    • https://dcicz.org/userfiles/file/99312109418.pdfIn PDF document text
    • http://graciaindoutama.com/kingkong/userfiles/files/67679984291.pdfIn PDF document text
    • https://rdw-wolf.de/backend/ckfinder/userfiles/files/88940705934.pdfIn PDF document text
    • http://perilatomsk.ru/ckfinder/userfiles/files/sinoj.pdfIn PDF document text
    • https://rtquery.reitoken.org/Coaching123/images/files/99381262227.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=different+face+shape+hairstylesPDF 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_off0000d953.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD953 17172 bytes
SHA-256: 2495c044e2c2238b8c0f4f6bf7006c8cddae78c8b94f87a5119de93d7fe79351
font_01_sfnt_off000105db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011df2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF2 10572 bytes
SHA-256: 7c1726da0eba18fbc580be8a23768bc88af8b8717b43932cc965885c73443ba4