Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac9d723058f74e08…

MALICIOUS

PDF

98.0 KB Created: 2021-08-26 05:23:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 66d297c245e767a2f689b0d9cc4896e0 SHA-1: 6922bb91e8db5d09dae5d9f78b519afad23ee8f4 SHA-256: ac9d723058f74e08b823d81b9af1342291829eb1485fad1199b353c90d1e0e91
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also functions as a link farm, directing users to numerous external URLs hosted on potentially compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://le-lemniscus-incandescent.fr/ckeditor/upload/files/63834893906.pdf In PDF document text
    • http://osrclass1967.com/clients/8/84/84e84eb3bb32f45446e669e24fea3ebc/File/66456289222.pdfIn PDF document text
    • http://fitviewer.de/files/file/16914574012.pdfIn PDF document text
    • https://susta.vn/userfiles/file/xukikojodexat.pdfIn PDF document text
    • http://gustosandvic.com/ckfinder/userfiles/files/84596788793.pdfIn PDF document text
    • http://atthaya.com/file_media/file_image/file/musonelukogoxurupipa.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bf13a93cddd---95991653752.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608da65f3eea5---negozutemawata.pdfIn PDF document text
    • http://smingames.com/ckfinder/files/50447426476.pdfIn PDF document text
    • https://samyenngochoang.com/wp-content/plugins/super-forms/uploads/php/files/tkje2ql4rtrkh5ac67r6rdvbq8/xiwapureki.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160de6f8804d93---mesamexu.pdfIn PDF document text
    • https://smartech.lv/sites/smartech/uploads/documents/files/56653884488.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/nfddlh6li4v3ed4qe1gkmmtii4/84031944330.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608a77833c700---53349036074.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/21126f3788bb48854d3f47cc36a2828a/41418146562.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16085902155cc3---gatubederavosuridisaki.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d64f87b7acc---45681165805.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/228cb504f2133111d6b662a84c57e13f/danopomigiwovupe.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/22197931266.pdfIn PDF document text
    • http://maduraicaterers.com/app/webroot/js/ckfinder/userfiles/files/polulitepafokopezosu.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/4522f16b71a3be3ac8772f80b2bece07/63433438006.pdfIn PDF document text
    • http://adhdesign.de/userContent/files/20210621132900-94651253572.pdfIn PDF document text
    • https://tonycustomtailoring.com/nbloom/fckuploads/file/zavusidigusu.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/kuguwamededanupoterel.pdfIn PDF document text
    • http://geoplan.su/userfiles/file/xopufefugedut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=ra+6713+implementing+rules+and+regulationsPDF 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_off00011a4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A4B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013262.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13262 11320 bytes
SHA-256: a64fd25ca63a6fe46891e190882bbde23e16aa553de631d23e13258a647ecff2
font_02_sfnt_off00014cea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14CEA 16916 bytes
SHA-256: 340c30f31c9526fabc2ef797b6cba80f805cb33022df8de2e63367ff04156af4