Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ca92dc6150946b5…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 19:49:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a30ea2087817e77f1cb970ab2e77759c SHA-1: 7e62aa4e13fdef236c640f62d90c2f624be221a4 SHA-256: 6ca92dc6150946b5155fd6970ecb30f28fe5e42479d6a8b993b0c7b968ba2471
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to PDF files on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links. While no scripts were explicitly extracted, the nature of the embedded URLs and the heuristics suggest the PDF is intended to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://mamtomchabahai.com/uploads/files/files/23908289499.pdf In PDF document text
    • http://ser-buk.com/userfiles/file/nilokolafexivadigiwamu.pdfIn PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210903_C693CD2AE60A5C2D.pdfIn PDF document text
    • https://youxsoft.com/uploads/files/rigosawo.pdfIn PDF document text
    • https://ckv-siemreap.org/ckfinder/userfiles/files/nixumep.pdfIn PDF document text
    • http://viorina-deko.com/images/file/lafojeluwu.pdfIn PDF document text
    • http://magiepourenfants.com/images/mediamanager/file/lidojud.pdfIn PDF document text
    • https://fundacionamigosdelmarcaribe.ong/ckfinder/userfiles/files/daxewevaja.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/161302e323504a---xewanen.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16142265f21fff---resal.pdfIn PDF document text
    • http://aibasylhet.edu.bd/app/webroot/ckfinder/userfiles/files/86914933116.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/fazulojiborolinuxo.pdfIn PDF document text
    • http://canadanur.com/resimler/files/65240499380.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/tizoja.pdfIn PDF document text
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/wukod.pdfIn PDF document text
    • https://calprin.com/ckfinder/userfiles/files/teguruvub.pdfIn PDF document text
    • http://alpinist.store/sribati/editor/uploadfiles/ganofesenijojomatu.pdfIn PDF document text
    • https://viboot.traigiongthuha.com/ckfinder/userfiles/files/36079310793.pdfIn PDF document text
    • http://gaudi.tw/upload/file/26634186520.pdfIn PDF document text
    • http://beta-rc.com/upload/files/mopeneduxujuzodefu.pdfIn PDF document text
    • http://paitoonbox.com/userfiles/files/gujisu.pdfIn PDF document text
    • https://dbmotorbrokers.com/userfiles/file/zesuwifigumur.pdfIn PDF document text
    • https://wedding-photos.cz/userfiles/file/siviwaradazufelifomusori.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=android+studio+development+essentials+pdf+downloadPDF 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_off0000d6fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6FE 17400 bytes
SHA-256: 8682b120fc4a8e1c7bb31dc065003cf6edb4d6f4d261d3bc5d4d1c312e4e02d2
font_01_sfnt_off00010470.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10470 10892 bytes
SHA-256: ce48538471798f42ae0fa70ff26c2ed23008a35ee0783c6014a98c9bec24c30e
font_02_sfnt_off00011db7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1