Malicious PDF — malware analysis report

Static analysis result for SHA-256 c258092e31f46954…

MALICIOUS

PDF

84.1 KB Created: 2021-09-16 19:34:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 13731051383ae3f447663d1815be8d23 SHA-1: e74ff4b0fd5e178a808b06a93559d703d63d41aa SHA-256: c258092e31f469540b6b6f50931e1d3fa183a5ef2fd7702030bf4f5fc8508d23
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier strongly indicated maliciousness. The embedded JavaScript likely facilitates the redirection or further malicious activity, while the link farm aims to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://medvor.ru/uplcv?utm_term=so+far+away+avenged+sevenfold+solo+tab PDF link annotation
    • http://adamlegal.com/userfiles/file/31542357276.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/65289723695.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/51509595675.pdfIn PDF document text
    • https://www.shamshabaddiocese.org/files/js/ckfinder/userfiles/files/54015232043.pdfIn PDF document text
    • https://airbays.com/userfiles/file/26957138645.pdfIn PDF document text
    • https://confidence-ist.com/ckfinder/userfiles/files/83214682516.pdfIn PDF document text
    • http://arenda-v-novosibirske.ru/ckfinder/userfiles/files/zawodot.pdfIn PDF document text
    • https://ecoolteh.eu/galeria/file/varuxaxa.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/60190577480.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/16130af1ae9b32---dematovaw.pdfIn PDF document text
    • https://ksmt.edu.np/assets/ckfinder/userfiles/files/sumemejomako.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/161322163ced2c---doresexonutovomebi.pdfIn PDF document text
    • https://www.liftechforklifts.com.au/application/third_party/ckfinder/userfiles/files/80986225675.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138c58bc8ef5---55810246597.pdfIn PDF document text
    • https://mcq-exambd.bdbabymart.com/app/webroot/ckfinder/userfiles/files/23593689634.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/goxaworixodomonevezit.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143107648ee4---75465506263.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161303de23e38d---xuwosuwavosijawoja.pdfIn PDF document text
    • http://bantinnhadat.com/users/files/19974142051.pdfIn PDF document text
    • http://fmmvn.net/userfiles/files/lolezewitugilabeweluli.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/18977341054.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/95371464182.pdfIn PDF document text
    • http://skupka54.ru/upload/m/fapuzigixasomini.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_off0000db9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB9A 19564 bytes
SHA-256: 78d7152fcf42476d3b6b9fd4fff9f281c09e85ca0165c103bf4f98e231fc0315
font_01_sfnt_off00010fa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127BF 10920 bytes
SHA-256: f26c5d0b1b4de5a7852e8a9cf68bfaa852c9956ee83012e2ddee69d73798ef05