Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c98db308d3d8d1f…

MALICIOUS

PDF

68.8 KB Created: 2021-10-03 20:30:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 034e6d1f7dee3e7b08e1018094d1f6ce SHA-1: a13834d5f2d697a6a61949ed113c6751948e8b89 SHA-256: 7c98db308d3d8d1fa092ad968f2803b9001cce8caa19c0af7096f708cd032968
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics point to the document being a link farm hosted on compromised CMS upload storage and disposable hosting, with numerous embedded URLs directing to potentially malicious content. The primary attack pattern involves directing users to external sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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.
  • 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://www.anoregmt.org.br/ckeditor/ckfinder/userfiles/files/10628446305.pdf In PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/61dpmcv7qtm921gsbai1q61d67/zerif.pdfIn PDF document text
    • http://marchmont.ru/imgs/file/96646041350.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/0e121fffd0487957d878e3b16ccdd5a0/povobabim.pdfIn PDF document text
    • http://betonkeritesek.eu/Content/files/96405087241.pdfIn PDF document text
    • http://logiccpacma.com/ckfinder/userfiles/files/vepotapuf.pdfIn PDF document text
    • http://vanprodukt.cz/UserFiles/File/59204125031.pdfIn PDF document text
    • http://rambud.pl/uploaded/file/48439045622.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16139bebf2e3fc---zinovupalakimejevunodaw.pdfIn PDF document text
    • http://tentimesneedlehill.com/UPFILE/userfiles/files/degosevaleditazajedaduzu.pdfIn PDF document text
    • https://goldfieldssanddrags.com.au/ckfinder/userfiles/files/24259582202.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/145489910614e1d32332a5.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/29169947594.pdfIn PDF document text
    • http://lumieye.com/userData/ebizro_board/file/joxufawobubimodutip.pdfIn PDF document text
    • https://contabilidadegoncalves.com/fotosempresa/files/78187786857.pdfIn PDF document text
    • https://diphong.com/uploads/19534436828.pdfIn PDF document text
    • http://ayrh.internet-match.com/upload/files/53502076562.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/161419389233c2---rigijidejowaweguboxujom.pdfIn PDF document text
    • http://cserepakciok.hu/xdata/file/perojunavewosavojoz.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/e083b8febb33769c7018bbfff191a0fa/pifokonumatugaferawog.pdfIn PDF document text
    • http://zulassungsdienst4you.de/bilder/file/domit.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=compassion+towards+othersPDF 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_off0000ad24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD24 15988 bytes
SHA-256: 8eec5dcb7e45bca158e991670d5b03e7ab4d90e03ab02897345e43c89e30950e
font_01_sfnt_off0000d5a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5A3 10728 bytes
SHA-256: a6624e2d72f35edbadd372126095904637ca91302a366eb2a5a5bbaf4802c7cc
font_02_sfnt_off0000ee2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1