Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f4023e68ea30d61…

MALICIOUS

PDF

82.2 KB Created: 2021-09-16 09:49:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ed2910dcc5ab574789ccc7bfc3de8efd SHA-1: 5ab1cbde18dab98c4384270df35f94134b43513d SHA-256: 8f4023e68ea30d61f132260c1656096380c4fc1ff51fa4871f1f816c6ef86bf4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and a link farm pointing to various PDF files hosted on disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript likely facilitates the download or execution of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://nesthomes.in/userfiles/file/51346858235.pdf In PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141f58b4a4dc---verolediwekojawexizufu.pdfIn PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/dofovivom.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/17669580569.pdfIn PDF document text
    • https://xn--80ag1a2a.xn--p1ai/files/file/niwuramojonalalu.pdfIn PDF document text
    • http://pincodehub.in/userfiles/file/29315720710.pdfIn PDF document text
    • http://abwclayton.com/uploads/files/84151644101.pdfIn PDF document text
    • https://suthuytinh.com/app/webroot/uploads/files/22616819644.pdfIn PDF document text
    • http://hagelkonzept.com/userfiles/file/niviba.pdfIn PDF document text
    • http://ntvietnga.com/upload/files/31223226996.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/olrvnm7hlgcrsik6aon0ubbvn6/jirovopiperudol.pdfIn PDF document text
    • http://wronba.com/uploads/wysiwyg/file/56060410338.pdfIn PDF document text
    • http://plkorea77.com/ckupload/files/34566234118.pdfIn PDF document text
    • http://quatangsongvan.com/hinhanh_fckeditor/file/68474614531.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16141dfe7a0f12---731022751.pdfIn PDF document text
    • https://nikunjfoundation.org/ckfinder/userfiles/files/56324238367.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/2c8cde681d677bb52313b75ce7b5c35b/99346084171.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/96939346073.pdfIn PDF document text
    • http://piannocreativo.com/js/new/fckeditor/userfiles/file/nobamorag.pdfIn PDF document text
    • http://finance-bulldog.cz/UserFiles/File/libisewofuxagemonawogo.pdfIn PDF document text
    • http://banglenhospital.com/UserFiles/File/situsazubawawewu.pdfIn PDF document text
    • http://nextlab-semi.com/files/fckeditor/file/gulaludezoxovatefol.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/84686095872.pdfIn PDF document text
    • https://www.geya99.com/ckfinder/userfiles/files/57864694877.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=download+texas+holdem+poker+apkPDF 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_off0000dbd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EC 10848 bytes
SHA-256: d76d77409746015bbb48d0fb7b00b12936f40fa6bf3c44aac73bf1513707fb17
font_02_sfnt_off00010cdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CDC 17904 bytes
SHA-256: 134462a7394cb09d4a77eff8456f4426784de011fe81735eb26e3af5802315e2