Malicious PDF — malware analysis report

Static analysis result for SHA-256 992168a2e7bef64e…

MALICIOUS

PDF

72.4 KB Created: 2021-09-10 14:23:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3bf56e3eb4b2e4c5bd7bc7aea0a72f35 SHA-1: 05b1273bd9e0f5c51260c5d7a9c8d15a30e536ef SHA-256: 992168a2e7bef64ee9ded329d24ae9b438e7e812eddc66f030990a64b95f852f
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, and it contains embedded JavaScript. The PDF also exhibits characteristics of a link farm, with numerous external URIs pointing to potentially malicious or disposable domains, suggesting an attempt to distribute further malicious content or phish users. The presence of embedded JavaScript indicates an intent to execute code, likely to download and run a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://bibliotheque-des-arts.ch/ckfinder/userfiles/files/gekigerananemon.pdf In PDF document text
    • https://chachachat.info/js/ckfinder/userfiles/files/rupunajaguxulemigeg.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/161309dcd385d4---65894431639.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/xidibujavopodogenaxuwe.pdfIn PDF document text
    • http://happinessgown.com/upload/users/files/zupitob.pdfIn PDF document text
    • https://cryptoshift.be/anaeter_capital/siteadmin/userfiles/files/bawuxajawajeguna.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/161388163bd2fb---47075750924.pdfIn PDF document text
    • https://dsverano.com/UserFiles/File/63297636336.pdfIn PDF document text
    • http://frezerovka.by/images/fxeditor/file/65224763821.pdfIn PDF document text
    • http://dkmmotor.com/files/userfiles/file/kikugoxagafoposexux.pdfIn PDF document text
    • https://nutricount.cz/UserFiles/File/tudusajixawogaxagag.pdfIn PDF document text
    • https://lenaoyunlar.net/calisma2/files/uploads/61060885604.pdfIn PDF document text
    • https://edubox.mn/uploads/users/0/files/wovenesosezefow.pdfIn PDF document text
    • http://bc-arman.kz/ckfinder/userfiles/files/43246097423.pdfIn PDF document text
    • https://a-1commercialkitchenservices.com/ckfinder/userfiles/files/51792726536.pdfIn PDF document text
    • https://jahanchart.ir/data/files/file/putotowimuwapomugowamesal.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/77826313559.pdfIn PDF document text
    • https://magnanerie-cazilhac.com/userfiles/file/16066829958.pdfIn PDF document text
    • http://ux02.wadhost.com/js/ckfinder/userfiles/files/45498878342.pdfIn PDF document text
    • http://tucsokszekszard.hu/images/news/file/toduvemuzojemewa.pdfIn PDF document text
    • http://www.kowel.com/ckfinder/userfiles/files/1631113168.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/86829465148.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/78590087231.pdfIn PDF document text
    • http://liga-stf.ru/i/upload/files/80015779.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+print+on+both+sides+pdfPDF 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_off0000bd8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d59e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD59E 14992 bytes
SHA-256: b16b74bafa45745c8da236c732bddc1eec13b94ce4227f16036783b099279dcf
font_02_sfnt_off0000fba4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA4 10604 bytes
SHA-256: aaa496bf72c77bc26c84c50b18b373d2fa3d37b6a30ad19dddbc629afae8ada1