Malicious PDF — malware analysis report

Static analysis result for SHA-256 b672a888d517fd18…

MALICIOUS

PDF

80.6 KB Created: 2021-09-23 10:18:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 941804169ed6405db7ece695165f12e5 SHA-1: ec6f33c0b121e04895fc9e60fc7b7601b3849f89 SHA-256: b672a888d517fd184f84d31e9d61df8147d24d873ae5743870b42c6beea5db22
134 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The document also features a large number of external URIs, many of which are hosted on disposable domains, suggesting a link farm or phishing lure. The presence of embedded JavaScript and numerous external links indicates an attempt to deliver a malicious payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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 https://crewmak.ru/uplcv?utm_term=words+that+start+with+b+adjectives PDF link annotation
    • https://kamarkosong.com/contents/files/79293215304.pdfIn PDF document text
    • https://machnik.net/ckfinder/userfiles/files/84637580482.pdfIn PDF document text
    • http://sieuthicayxanh.vn/webroot/img/files/falimudusodogebepekoko.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136f54d5106d---wujuxidos.pdfIn PDF document text
    • http://rrarental.org/upload/file/zerugirajox.pdfIn PDF document text
    • http://n2nlah.org/UserFiles/file/75565726080.pdfIn PDF document text
    • http://pitin-akutsu.com/js/upload/files/81269000238.pdfIn PDF document text
    • https://ekransamara.ru/files/pozexurerovafowepa.pdfIn PDF document text
    • https://andrejc.si/files/file/kevaturixudupubo.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/losojulidaxajexofiwawig.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/romagotetep.pdfIn PDF document text
    • https://cauthinh.com/luutru/files/xarozefegaxifefik.pdfIn PDF document text
    • http://offerseir.com/basefile/offerseircom/files/repadanawavava.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133fe3257202.pdfIn PDF document text
    • http://gasasosong.com/upload/fckeditor/file/21058326455.pdfIn PDF document text
    • http://lpc2529.com/piceditor/file/35137397030.pdfIn PDF document text
    • https://eminencesolutions.in/resources/userfiles/file/64379817645.pdfIn PDF document text
    • http://it-hair.com/userfiles/94696821041.pdfIn PDF document text
    • https://bonaparte.cappencms.com/templates/files/laredudaninarewaxe.pdfIn PDF document text
    • http://dealershop.es/userfiles/file/25034049112.pdfIn PDF document text
    • http://eros-arena.de/eros/userfiles/file/38432291194.pdfIn PDF document text
    • http://xinyuemu.net/assets/202109/files/20210907212841637568.pdfIn PDF document text
    • http://edu-soft.ru/site/htmlimages/file/34278316072.pdfIn PDF document text
    • http://rhondadejean.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/58595105008.pdfIn PDF document text
    • 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_off0000d734.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD734 10732 bytes
SHA-256: 441760571b01c2dce3fc07d3786ca16b3ccf6164b3c3714ee9b8b56dbe39ceeb
font_01_sfnt_off0000f001.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF001 16960 bytes
SHA-256: 2429eda12a206ce30fe4e676d8a148ca44cd0b1d0ca5e90a8428f57e36113d4d
font_02_sfnt_off00011c26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1