Malicious PDF — malware analysis report

Static analysis result for SHA-256 b021d12da7a5f911…

MALICIOUS

PDF

71.7 KB Created: 2021-09-20 05:08:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6168378840a33cf6e462e52ef022946c SHA-1: d5cd03f8d06f7d8adf2ef8893b51710c7624cb9e SHA-256: b021d12da7a5f9117572b0711066da29f88162f66c799ea8c308c28a0c6588da
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users to malicious content. The ML classifier also flagged this PDF as malicious. The presence of JavaScript suggests an attempt to execute code, likely to facilitate further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • 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 https://crewmak.ru/uplcv?utm_term=capcut+for+pc+apk PDF link annotation
    • https://deycaterers.com/ckfinder/userfiles/files/69717204518.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/13204827778.pdfIn PDF document text
    • http://archissimo.eu/userfiles/files/26377403051.pdfIn PDF document text
    • https://ixiu-23.com/uploads/files/202109101114315730.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16137bd9a4cfe7---57757594256.pdfIn PDF document text
    • https://www.sonorisation-auxerre.fr/ckfinder/userfiles/files/70142634469.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/1747461332.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/begomawegegazij.pdfIn PDF document text
    • http://demo-enriquemora.shopcloud.es/ckfinder/userfiles/files/koxexaronetavisarejepowu.pdfIn PDF document text
    • http://parikshitconstruction.com/uploads/tenewatufelos.pdfIn PDF document text
    • https://frisch.ro/files/file/67452625199.pdfIn PDF document text
    • http://epoch-making.jp/js/upload/files/86441344107.pdfIn PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/wejawikizonevajefipi.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/kufiworumukekitex.pdfIn PDF document text
    • http://hondatayho.top/img-ngocbao/files/40710722977.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/qj9ae8dkr8ms7jqtcg0j88m96k/30120121530.pdfIn PDF document text
    • https://9ja-bet.com/userfiles/file/6968240828.pdfIn PDF document text
    • http://crisismobile.com/ckfinder/userfiles/files/sawuzuxuw.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142553eb2549---86329094845.pdfIn PDF document text
    • http://daming-school.com/userfiles/file/pojuxonufijuxomoxa.pdfIn PDF document text
    • https://graveyards-fuj.ae/userfiles/files/78192639831.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b6cfc8429e---84834915892.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_off0000b3c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3C5 10156 bytes
SHA-256: ad8d461ebc90c5684ce4a2d42ae39294ad853033fc0b076b066933834b28f5f3
font_01_sfnt_off0000caa7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAA7 18284 bytes
SHA-256: b34e28cb6d651703f95dfb4f1641f1107dcb7e44359f7990f62937913fa4475f
font_02_sfnt_off0000f959.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF959 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1