Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f955b825ac89834…

MALICIOUS

PDF

80.6 KB Created: 2021-09-16 01:37:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 27b36ef065eec82b6ba645917d51ebda SHA-1: 02d68ff54aa9e826968a4fc054eaedae96edbdf1 SHA-256: 5f955b825ac8983451d48b8dcf73a5b09e74c69dfd22c2215c013392c9c7391e
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to URLs hosted on compromised Content Management Systems (CMS) or disposable domains. This behavior is indicative of a link farm designed to redirect users to potentially malicious content or phishing sites. The ClamAV detection and ML classifier further support its malicious nature, likely as a phishing or trojan delivery mechanism.

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://myjobcareer.net/userfiles/file/2021090615423273499.pdf In PDF document text
    • http://plechotice.sk/tmp/file/8335642970.pdfIn PDF document text
    • http://basaritarim.net/admin/editor_resim/file/gisinuku.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/21532816142.pdfIn PDF document text
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/fetefonevozir.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/41019462446.pdfIn PDF document text
    • https://ximatinhdongnai.com/app/webroot/files/images/pages/files/10883671705.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/228b81fee90d74b5a5d29003b34d47a5/3771843217.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/zoganalijaremizegesaj.pdfIn PDF document text
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/biwumakulobaj.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/xaponugozumesidi.pdfIn PDF document text
    • http://bhk-aindling.de/userfiles/files/fijofedogaz.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/2ab94de915fe3a5b4b5df2f2dd7d4e08/9192230144.pdfIn PDF document text
    • http://tatvideo.ru/ckfinder/userfiles/files/28540070604.pdfIn PDF document text
    • http://kahasat.cz/data/file/nataxomojezulavuxabivafox.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/ophldnfif2p347essfk0vnj3i5/bugifisajugi.pdfIn PDF document text
    • https://ecohort.info/userfiles/files/74774495923.pdfIn PDF document text
    • https://goldmenu.com/userfiles/file/luzaveduwasaxavikozo.pdfIn PDF document text
    • https://rewaqousha.net/userfiles/files/95254244954.pdfIn PDF document text
    • http://equipociclistaugeraga.com/ciclistas/userfiles/file/wosaleloluromapavoxurum.pdfIn PDF document text
    • http://getrade.net/uploadfiles/file/pivubuwogog.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d9a6032c9---furimaruzajatabefidoli.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/bovukesativibelupodup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=beautiful+granny+analPDF 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_off0000d410.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD410 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC27 10368 bytes
SHA-256: bae512156ca3d8154a3d90cd8fdb3f694db7b9a70a280d33c19658ac769a4d40
font_02_sfnt_off000103b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103B0 18664 bytes
SHA-256: 855056b39c03aa6182dd028716df6900e8673bf0efe31ca129157c6cb143d511