Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9c3d45106ccf056…

MALICIOUS

PDF

104.0 KB Created: 2021-07-13 17:58:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 0c8699d24af0791bd7f2630b07df496a SHA-1: d351885e7a106d975e9bad5458c581b677e21a7f SHA-256: e9c3d45106ccf056469d334e950088a5e5dfb8e799a470db2dbc01fa9f6a3a5c
236 Risk Score

Malware Insights

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

The PDF document contains numerous links to external websites, many of which appear to be compromised WordPress installations. The 'SE_BROWSER_INSTALL_LURE' heuristic indicates the document is designed to trick the user into installing a fake browser extension or update. ClamAV also detected the file as 'Pdf.Phishing.Trojan'. The presence of embedded URLs and the ML classifier's high confidence score further support the malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9790

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • 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://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/44bf7c791acc1399ad14fe7a153362c4/46837530404.pdf In PDF document text
    • https://101doctor.com/uploads/ckfiles/files/60e2c985bc710.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/7vtgpih6jq298cj9nc46f1pti8/benosomikoxunazamopakif.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/290949012928.pdfIn PDF document text
    • http://szkolaprywatnaleszno.pl/userfiles/file/lisexapuvilupu.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2967e7fafc---ribezolawu.pdfIn PDF document text
    • http://africareview.in/userfiles/file/58501874900.pdfIn PDF document text
    • http://oio.cn/uploadfiles/files/godipokevonufejajapa.pdfIn PDF document text
    • http://thehonourride.ca/clients/c/c2/c2a221447f3e921143a55eca482c8289/File/jikowab.pdfIn PDF document text
    • http://www.heksan.com.pl/file/15216889592.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/n7vo7b2gquj2vja6au1klgd2t1/88004072364.pdfIn PDF document text
    • http://duonglaohanoi.com/userfiles/file/28283125771.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1606d24db09641---18473098937.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/silakotumozisolojufinosob.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/38689b008ad4e3b39187776d8dfc8d04/36465041463.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a7cca8a6984---2333173817.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160c34dd78b39b---voduwatigebi.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ac31bf4a979---98093374516.pdfIn PDF document text
    • http://fluitec.fr/ressource/site-image/files/74524939823.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/b9d893544b5b0fb5753ace6b1785229e/47786563929.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a59a62a2c21---73824870551.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/idana74ooeu6re79v9ll1smb61/65204660306.pdfIn PDF document text
    • http://mientrungland.net/uploads/image/files/sizijosisidovuxe.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb1c47c808---53032791685.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16092873f7ea65---74166346031.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/17469019321.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=download+file+extension+chromePDF 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_off000134a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134A8 17208 bytes
SHA-256: f941e7d21d68819b058a652b06eda6195c032526983f771d2375ba77249c0829
font_01_sfnt_off0001614f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1614F 10928 bytes
SHA-256: 12f3f2c1a3ef239a7bf0237409435d67d524f14bdf36b7ca94a2340f21815dc7
font_02_sfnt_off00017a7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17A7F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1