Malicious PDF — malware analysis report

Static analysis result for SHA-256 10bd57cd6063490b…

MALICIOUS

PDF

77.3 KB Created: 2021-10-10 03:08:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: faca3c205a8c6ed12a26e9b52a7e5924 SHA-1: 1e135870a4f6f0e9655d8ed70755b49a036cca9c SHA-256: 10bd57cd6063490b1ef7ca7abc9db4f06cb3a3304c622fbf035a64e82730c7e1
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, indicating a malicious intent. The heuristic 'SE_CALLBACK_LURE' strongly suggests a callback phishing or tech-support scam, where the user is prompted to call a number. The ML classifier and ClamAV detection further support the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://synerhu.ru/uplcv?utm_term=hypothermia+and+headache PDF link annotation
    • http://premo.at/userfiles/file/vonuraxafiguwenesajemew.pdfIn PDF document text
    • https://cezartravel.hu/userfiles/file/35627103551.pdfIn PDF document text
    • http://www.sainteuphrasia.com/www/js/ckfinder/userfiles/files/bijavupimivumonafob.pdfIn PDF document text
    • http://www.protectakoteasia.com/ckfinder/userfiles/files/33077632883.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137f35eb7e97---79545537720.pdfIn PDF document text
    • http://jfe.hk/userfiles/povanipizi.pdfIn PDF document text
    • http://studiopiergentili.it/userfiles/files/87871706228.pdfIn PDF document text
    • http://cgemfoco.com.br/ckfinder/userfiles/files/86810445077.pdfIn PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/jevina.pdfIn PDF document text
    • http://tfforming.ru/d/files/sutakufejipajujile.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343fe817538---68467826913.pdfIn PDF document text
    • http://haitrungkim.vn/uploads/userfiles/file/15207664988.pdfIn PDF document text
    • http://e-district.org/userfiles/file/87954678584.pdfIn PDF document text
    • https://khachsan295doson.vn/namthuan/images/news/files/pidepepozavimumevu.pdfIn PDF document text
    • https://smilaxlabs.com/userfiles/files/buninobutazokeni.pdfIn PDF document text
    • https://mingyi-lock.com/data/file/userfiles/files/39827242668.pdfIn PDF document text
    • https://lyonsinn.com/nbloom/fckuploads/file/63713235700.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/zamitivesulenesesegisele.pdfIn PDF document text
    • http://www.pataniforum.com/admin/jquery/ckfinder/userfiles/files/lesoxudodejetijarowabatok.pdfIn PDF document text
    • https://bibonatura.com/ckfinder/userfiles/files/52885878958.pdfIn PDF document text
    • https://get-insurance.in/ckfinder/userfiles/files/72322960355.pdfIn PDF document text
    • http://cisseo.net/userfiles/files/nagikesirivan.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/23998339350.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_off0000cc25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC25 17100 bytes
SHA-256: 6a5a7c1c61af3996ffa02612a87d1f1d9190ec9ae6b9d4d453b851aea34ac20e
font_01_sfnt_off0000f751.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF751 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F68 10672 bytes
SHA-256: 2d8d01ebd49d6c2cf4df71ad23c22784b04eee78063a75f65b0663b723430930