Malicious PDF — malware analysis report

Static analysis result for SHA-256 250c4caba86ed18e…

MALICIOUS

PDF

81.0 KB Created: 2021-10-07 04:48:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 639d5033a076335214acd7e66b7ec3aa SHA-1: b002ac303786cf670608df1ca7147d7565269144 SHA-256: 250c4caba86ed18e7d3b1ced6e3853b46f1f994687b2a1de61f636614abeef5f
134 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, with critical and high severity heuristic firings. It contains embedded JavaScript and numerous external URIs, indicating it's designed to redirect users to potentially malicious websites. The PDF structure and the presence of JavaScript suggest an attempt to exploit vulnerabilities or deliver further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://inwebjor.ru/uplcv?utm_term=can+sleeping+too+long+give+you+a+headache PDF link annotation
    • https://ccskin.com/geektic/files/mufazokinamofozulego.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/ce80a6487b9d791949d98e90073a91d4/zejanerav.pdfIn PDF document text
    • http://www.palmettoexpresslanes.com/system/js/back/ckfinder/userfiles/files/bubajurusoduj.pdfIn PDF document text
    • http://neonatal-surgery.ru/userfiles/files/16425860286.pdfIn PDF document text
    • http://nowator-zpu.pl/userfiles/file/44566684675.pdfIn PDF document text
    • https://manusingh.org/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/40127115185.pdfIn PDF document text
    • http://accapierre.it/userfiles/files/morow.pdfIn PDF document text
    • http://kubabus.cz/novy-web/upload/file/16957051527.pdfIn PDF document text
    • http://e-sheremet.com/img/19698860423.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/90856818242.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/files/vulubamanalosubofefam.pdfIn PDF document text
    • http://dichvubaove.online/upload/files/duwibon.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614fc8a7da46d---vajijatapowixefadur.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/18747774223.pdfIn PDF document text
    • http://thegioixedap.net/upload/files/74324827445.pdfIn PDF document text
    • http://www.lircai.com/web/inline/file/21983434774.pdfIn PDF document text
    • https://viessmannboilers.ca/fck_upload/file/gojozegirozoxozag.pdfIn PDF document text
    • http://benevolo.it/userfiles/files/momek.pdfIn PDF document text
    • http://chongros.com/userData/board/file/8602638198.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210910010510.pdfIn PDF document text
    • https://autotoner123.com/home/autotone/public_html/ckeditortest_WORKING/ckfinder/userfiles/files/jujitivamejewefulu.pdfIn PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/41388831859.pdfIn PDF document text
    • http://rialta.ie/userfiles/files/39593646707.pdfIn PDF document text
    • https://moolans.com/uploads/files/loxafomijajizebepupepox.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_off0000d983.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD983 11004 bytes
SHA-256: d98bee41ecf9c20e90d6c448021243dc7bfa9980aac9b51c3680c74cfadc6dfe
font_01_sfnt_off0000f2e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010af6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AF6 17188 bytes
SHA-256: 190a53e829ce40be581e18a7cc6218ed8a3dc94b40c0212be6ef93e8c7c07f11