Malicious PDF — malware analysis report

Static analysis result for SHA-256 b34598b1d0e1f686…

MALICIOUS

PDF

83.6 KB Created: 2021-09-23 01:23:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 5035056a4a0a704b01a5dcb5966231af SHA-1: d061e68164dfb809db7c8e5c19e2f582de4df17e SHA-256: b34598b1d0e1f686f29b4a3635ae358daf33d92239424ae27ff22b0087608a28
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ClamAV and an ML classifier, with high confidence. It contains embedded JavaScript and multiple external URIs, including one pointing to 'queure.ru' with a 'brawl stars new update apk' UTM term, suggesting a lure for potentially malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a link farm strategy, further supporting the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://queure.ru/uplcv?utm_term=brawl+stars+new+update+apk PDF link annotation
    • http://johnmarzillier.com/ckfinder/userfiles/files/wusumuzanekeva.pdfIn PDF document text
    • https://brakos.it/file/fapivekukijonotare.pdfIn PDF document text
    • http://fizjoactiv.eu/Upload/file/tekuso.pdfIn PDF document text
    • http://kimwendelldesign.com/ckfinder/userfiles/files/22781795373.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/90512512903.pdfIn PDF document text
    • https://educhina.mn/editor/files/bedakeko.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/muxidufiwux.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/tepulavem.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/64722792487.pdfIn PDF document text
    • http://julianowka.pl/ckfinder/userfiles/files/xamififuleb.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/22280327420.pdfIn PDF document text
    • https://flyags.com/editorResources/file///52926024762.pdfIn PDF document text
    • http://piazzademarini3ge.com/userfiles/files/97460087723.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/vagijadamozis.pdfIn PDF document text
    • http://ricarda-allegra.de/userfiles/file/78574518718.pdfIn PDF document text
    • http://conniecorsentino.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jugowakaxiterobon.pdfIn PDF document text
    • https://equalitas.es/userfiles/file/68152214247.pdfIn PDF document text
    • https://attackworkoutprogram.com/app/webroot/files/ckfinder/userfiles/files/26755613582.pdfIn PDF document text
    • http://chickenwild.com/upload/contents/images/images/72995922233.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/15f69d3419fffeffbed3fe2683f9e95c/44460425313.pdfIn PDF document text
    • http://phonphangschool.com/upload/files/gefikomapi.pdfIn PDF document text
    • https://nistd.in/userfiles/file/91091726049.pdfIn PDF document text
    • https://www.algeos.com/js/ckfinder/userfiles/files/demapuvuxupunu.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/kubafamazozubefu.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/ruwexalulofutokos.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_off0000d7ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7AE 10504 bytes
SHA-256: ed293fc59a0311bf388fb5b948ef94204742c7b3316b2544b3c2dff384e4b76e
font_01_sfnt_off0000efce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E0 21876 bytes
SHA-256: 42b0ee1f3125fdacc35cb272edc8bf9926ed0596fd3b9100708ce6035408b35b