Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8b9963f663589cf…

MALICIOUS

PDF

82.4 KB Created: 2021-09-19 18:50:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2f340071cbea9d9e382c511642834dd3 SHA-1: b0c499a54354a80d154ea35f00ff05d19575d39e SHA-256: f8b9963f663589cf830893e7b9ccb82794d810ff7149ce918d6c7d8afaf6fac6
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high ML score and ClamAV detection. It functions as a link farm, containing numerous embedded URLs pointing to various domains, many of which are associated with compromised CMS uploads or disposable hosting. The primary purpose appears to be directing users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://nuovojob.com/userfiles/files/42666668557.pdf In PDF document text
    • http://nutranghongngoc.com/media/ftp/file/dufovebovuzowosifoz.pdfIn PDF document text
    • https://habibitours.net/ckfinder/userfiles/files/58224505645.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210909201232.pdfIn PDF document text
    • http://adria-ex.com/images/blog/file/mewufumusemupebegaxonu.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/53471646012.pdfIn PDF document text
    • http://fourfoods.com/images/files/wepezerajogazipipesuzu.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6285cf922---78942355897.pdfIn PDF document text
    • http://msdoubrava.cz/foto/images/file/99754956672.pdfIn PDF document text
    • http://tahi.hu/ckfinder/userfiles/files/45664863958.pdfIn PDF document text
    • http://gardenofsound.com/userfiles/files/55837633827.pdfIn PDF document text
    • http://i-physiology.ru/upload/57590718589.pdfIn PDF document text
    • http://nzozkrowodrza.pl/uploads/editor/file/8128624371.pdfIn PDF document text
    • http://jsqnchem.com/upload/files/59274639506.pdfIn PDF document text
    • http://fvv-hohenfelde.de/sites/default/files/files/58224073946.pdfIn PDF document text
    • http://kamnitikamini.si/upload/files/75133024545.pdfIn PDF document text
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/71634341054.pdfIn PDF document text
    • https://fanaf.org/article_ressources/file/kibazowemasalumel.pdfIn PDF document text
    • http://codienlanhtrangia.com/Images_upload/files/59510855624.pdfIn PDF document text
    • http://crisismobile.com/ckfinder/userfiles/files/43512750435.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16145dcf8be88a---63331842016.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1614359885b0cf---gufiga.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/gowifamew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=thermal+manager+androidPDF 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_off0000cd1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e52c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52C 23796 bytes
SHA-256: 44cd24610d8ccfb98404dfd1a2ebcf63771304f79b491204147ee8006a566670
font_02_sfnt_off00012397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12397 10392 bytes
SHA-256: eee54c46d81c48d5c6d93117b827da5cb48669dc14e389bde8e54f8c45e33879