Malicious PDF — malware analysis report

Static analysis result for SHA-256 eb9d45dbe3e470b4…

MALICIOUS

PDF

75.9 KB Created: 2021-09-24 04:56:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0a40dd8f4dbc7031e0e901352d49fec5 SHA-1: c162aa856ebe6d0a9dd2e6c3ca98a351e59d1ff2 SHA-256: eb9d45dbe3e470b41f6fa95b914ef8fe66b4a2ced01778a72b91bdbffb1caa21
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting and employing UTM parameters, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards it being used to redirect users to malicious websites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • 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.
  • 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://laborke.ru/uplcv?utm_term=download+norwegian+wood+pdf PDF link annotation
    • https://netpage.info/userfiles/file/remevedexupogafefuwog.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/guson.pdfIn PDF document text
    • http://nsk-nalogov.net/upload/files/gozebazusivin.pdfIn PDF document text
    • http://ministryofrum.com/memlogos/file/bokuvexefanemosaba.pdfIn PDF document text
    • http://churchtextile.com/userfiles/file/senazapekokubelotixoso.pdfIn PDF document text
    • https://manusingh.org/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/raramolidisegilosofa.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e7ca494a4---fijopa.pdfIn PDF document text
    • https://charterboatdeliverance.com/uploads/files/bimaz.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613145ba4975c---gukokepirugedemu.pdfIn PDF document text
    • https://spacio.hk/attachment/file/24711927805.pdfIn PDF document text
    • http://daydeothe.vn/rich_editor/file/16906893583.pdfIn PDF document text
    • https://autoprofi.ua/userfiles/file/jaronepoj.pdfIn PDF document text
    • https://dogathermalhotel.com/resimler/files/jabalewetaveb.pdfIn PDF document text
    • http://www.otevrenysklep.cz/ckfinder/userfiles/files/remidobewuvotulezibek.pdfIn PDF document text
    • http://dongamold.com/fckeditor/upload_files/file/tewuraz.pdfIn PDF document text
    • https://digireg.cz/upload/pezejefudofivuvuma.pdfIn PDF document text
    • http://cistenivytahu.cz/upload/file/dorusiwisol.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/wodogun.pdfIn PDF document text
    • http://bndweb.nl/upload/files/21364430024.pdfIn PDF document text
    • https://sanipro.ma/app/webroot/uploaderfiles/lomijevivutujatisenagom.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/202198210416988.pdfIn PDF document text
    • http://sdhmladavozice.cz/userfiles/file/84685927774.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/37593346186.pdfIn PDF document text
    • https://cjsc.se/ckfinder/userfiles/files/30519753471.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_off0000c066.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC066 19216 bytes
SHA-256: 4385875cdf914e00609a8bedd7d043827d0aca6b73855e5f8a3381ab29065fab
font_01_sfnt_off0000f23c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A53 10492 bytes
SHA-256: fa47c536d0b02a9ce8c3aa087409394f91c4110aceb0f82c740d6c9dbbfdaa59