Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f993d6272bf7923…

MALICIOUS

PDF

73.3 KB Created: 2021-08-13 14:52:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 901f08f0c8d887e3538f33d91618461a SHA-1: daee899c43f7e5a1c0dc50058ee52a1ab38cd58a SHA-256: 8f993d6272bf7923971dd977cfa823cf0b3b61e069380c71981b7541327aedc4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct user-facing content but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://palazzodiaz.com/userfiles/files/66873068121.pdf In PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c70abef23---jafatot.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab97efb20ca---gajeliseneb.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/fd18699d84687fafab5d1bc5cf2cbc77/fogebiw.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/82791796451.pdfIn PDF document text
    • https://butagallery.com/userfiles/files/3166771994.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/10d4f35898044d6cb1927d52118c6728/rejobavipel.pdfIn PDF document text
    • http://roland-toys.eu/userfiles/file/lesajara.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce3278d2c3---nosikuzofegelobikatubi.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/217659328.pdfIn PDF document text
    • https://mylodge-naoshima.com/nijavobolatopanov.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c421572af3b---berobutaloloxazulurorawux.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad2e5ec056a---34865408322.pdfIn PDF document text
    • http://churchontherockuk.org/home/churchontherock1/public_html/userfiles/files/vivig.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/4ad116777143e5a16984949603fbbbda/51192657013.pdfIn PDF document text
    • https://przyklejki.pl/userfiles/21816463296.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=mapa+conceptual+transporte+de+la+membrana+celularPDF 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_off0000b83a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB83A 10816 bytes
SHA-256: 5f6009cc9f259f00378d6af0bc341979a30df907c1e816e89b61e63fd3ab86b0
font_01_sfnt_off0000d0fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e90f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE90F 17600 bytes
SHA-256: ca22a3ca1e4308d95172de035037a250f0e6d6a5d0e1ee36f3707189747fa1da