Malicious PDF — malware analysis report

Static analysis result for SHA-256 99362a3cbb8e89d5…

MALICIOUS

PDF

94.0 KB Created: 2021-09-12 13:27:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 789aa204ac2c47009eb70e96a37c2118 SHA-1: 9dbd5ef65e1f5a5372bbe01fdd30496e6080eebb SHA-256: 99362a3cbb8e89d541bd861122facfb887a192e42649c25a9aab06468de4ebf5
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains embedded JavaScript, which is often used to redirect users or download additional malicious content. The presence of numerous distinct external URIs, many pointing to PDF files on various domains, further supports a phishing or link-farming attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://burragebrothers.com/demo/jolie/beta/userfiles/files/92732667573.pdf In PDF document text
    • http://khautrangkhangviet.com/upload/img/files/xikerasuxe.pdfIn PDF document text
    • https://zagorjeadventureteam.hr/files/56163171938.pdfIn PDF document text
    • http://dynamic1984.com/user_file/file/49074354322.pdfIn PDF document text
    • http://xn----7sbev0bhje.xn--p1ai/images/news/file/32585506459.pdfIn PDF document text
    • http://cosonhuath.com/hinhanh_fckeditor/file/tufojemigema.pdfIn PDF document text
    • https://mmgrowersg.com/ckfinder/userfiles/files/kebuzun.pdfIn PDF document text
    • http://nanchang.chinatupai.com/web/js/ckfinder/userfiles/files/3606222942.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/79599246001.pdfIn PDF document text
    • https://taptigrihnirman.com/singhania/downloads/file/87095132007.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/mubizog.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/86006034890.pdfIn PDF document text
    • https://grouptm2.com/contents/files/25121568830.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/17554527807.pdfIn PDF document text
    • https://upbfassadenbau.com/upload/file/duwavuvonaru.pdfIn PDF document text
    • http://akvatoria.by/UserFiles/files/11409181673.pdfIn PDF document text
    • http://cardealer-space.com/js/upload/files/13087912629.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303c3119a0d---bataxewomel.pdfIn PDF document text
    • http://bbmeti.it/userfiles/files/jarosutixupaxid.pdfIn PDF document text
    • https://songhong.info/userfiles/file/rizaxupunar.pdfIn PDF document text
    • https://makenie.com/upload/files/19195980943.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/26432006008.pdfIn PDF document text
    • http://przyrodnik-kujawy.eu/userfiles/file/89993744815.pdfIn PDF document text
    • https://pediatricpotentialsnj.com/PP/PPpng/files/wabajovalokipixezex.pdfIn PDF document text
    • https://claudiodituri.it/uploads/jovefexigexes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=ad+blocker+for+android+browserPDF 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_off000105f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F0 10668 bytes
SHA-256: 35016d624c3256bf8941eda01799c147c2669d11eee29f26fcb67b9b2d0c7443
font_01_sfnt_off00011e90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136A2 19684 bytes
SHA-256: 1208964efcacff68d8d3adad8aa02602bd6241dfcaadba6063f9f172ebe30513