Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b5e583ccac66207…

MALICIOUS

PDF

78.7 KB Created: 2021-09-13 09:57:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4c0bc41c67f24a317c71ab96d982e683 SHA-1: 99d916181ef5b9da89f5ab70c63cc11bbb7fe791 SHA-256: 7b5e583ccac66207c6ce6167bb6f589cd607e8e2a89b47c4e59f673fe2bb843c
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 features numerous external URIs, many of which point to compromised websites or link farms, suggesting an attempt to distribute malicious content or phish for information. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • 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 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://tchid.net/userfiles/file/18986045532.pdf In PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5ba9ad4c4---zusujadiwugufezekes.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/8442832669.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/dozoladalanib.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/jobinuz.pdfIn PDF document text
    • https://behagi.eus/files/galeria/files/gekitozexela.pdfIn PDF document text
    • http://cuborh.com/natelinhanew/js/ckfinder/userfiles/files/74839905931.pdfIn PDF document text
    • http://jljemc.com/upload/files/9860606669.pdfIn PDF document text
    • http://studiomarcheluzzo.it/userfiles/files/wojubixazewixutuvuwipe.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109010334002716.pdfIn PDF document text
    • https://daulte.ch/ckfinder/userfiles/files/84843755881.pdfIn PDF document text
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/68686277494.pdfIn PDF document text
    • http://24cvety.ru/upload/files/japozotilisaloro.pdfIn PDF document text
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/bonamuk.pdfIn PDF document text
    • http://wwstationery.com/files/file/sitab.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/6d163450ecf0cf9de67cf7482f56dcbe/26456370395.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/nuwedoboxovezib.pdfIn PDF document text
    • https://tidymoney.com/ckfinder/userfiles/files/fotixajowirepuboduxiwudow.pdfIn PDF document text
    • https://danielstrehlau.com/userfiles/file/21774207180.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/7fbbb14af338e80b1d9b69c7582a4320/kigopuninapebuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=download+among+us+for+free+windows+10PDF 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_off0000d2ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2EF 10960 bytes
SHA-256: ba3849a6f9100b3eb929fd1dd70b10de465f2522d985c8dfab75a1c8be2eb0ba
font_01_sfnt_off0000ec34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010446.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10446 16084 bytes
SHA-256: ba79799b991341c49e6eeec325be1f7c514a0d2ee03826482c1c6f50f9b900c9