Malicious PDF — malware analysis report

Static analysis result for SHA-256 51e336e5e5ec3f8b…

MALICIOUS

PDF

85.3 KB Created: 2021-09-20 07:35:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6d812168e45bfdbd47adef7afb69ffeb SHA-1: 31b28ffba9b3563a2a818b27aeee4f8831ebaa25 SHA-256: 51e336e5e5ec3f8be2ac99582e9ed2b324678438ac60b02c17e33193698a81c4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised CMS upload storage, indicating a link farm designed to redirect users to potentially malicious content. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • 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 http://doubler-son-capital.com/photos/files/32462788092.pdf In PDF document text
    • https://autotoner123.com/home/autotone/public_html/ckeditortest_WORKING/ckfinder/userfiles/files/bifomidizaxe.pdfIn PDF document text
    • http://ckudzcssffhhj.handysociality.com/upload/files/mezamobezevusuge.pdfIn PDF document text
    • http://mebelhotel.ru/userfiles/files/77032763901.pdfIn PDF document text
    • https://tckontrola.hr/files/kifodonusuwizovisalumaxu.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/pipugasujuvagewevuf.pdfIn PDF document text
    • http://telecycling.info/files/file/romugevovepuvovogik.pdfIn PDF document text
    • http://sindikat777.ru/ckeditor/ckfinder/core/connector/php/uploads/files/norigoka.pdfIn PDF document text
    • http://aktien-analyse.de/images/File/gitunixojemitifakiraramag.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/15412776725.pdfIn PDF document text
    • http://amandatour.ru/js/ckfinder/userfiles/files/robekekinen.pdfIn PDF document text
    • http://mueblesdepladur.es/1/userfiles/file/rofudulobuwu.pdfIn PDF document text
    • http://veewood.com/file_media/file_image/file/guxogawixa.pdfIn PDF document text
    • http://medicare-darmstadt.de/bilder/UserImages/file/xarufu.pdfIn PDF document text
    • http://bulongvungtau.com/media/ftp/file/35538150314.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/425e168fa4e5c5859eae6aac278e3a92/gunidabokelid.pdfIn PDF document text
    • http://secretinvitation.net/images/files/67510521320.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139241a70867---99988140212.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1614138078a8e1---36556779194.pdfIn PDF document text
    • http://colokit.thienlonggroup.com/Images_upload/files/pavirinuvanuwurezebowiba.pdfIn PDF document text
    • http://behtarinekhodetbash.com/files/files/93913847147.pdfIn PDF document text
    • https://cantarefides.ro/admin/userfiles/file/siveginavipowir.pdfIn PDF document text
    • http://condosworld.com/abisol1/userfiles/files/43313910899.pdfIn PDF document text
    • https://santa.my/images/users/00000000/files/mapalaxikurogef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=demon+slayer+us+releasePDF 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_off0000e88e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE88E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A0 18152 bytes
SHA-256: 964493738100c7cd5a09953efdbd2a7494f3fadca67b61af085c3e64e52659d1
font_02_sfnt_off00013029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13029 10292 bytes
SHA-256: 83a7483caa89c246908bb27f9651f00cce702ef79d86f0fd97a92291be684979