Malicious PDF — malware analysis report

Static analysis result for SHA-256 af9fe0d607f0530f…

MALICIOUS

PDF

85.7 KB Created: 2021-08-23 14:08:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c3a80b6f705ff7db3a414d8e4ee61077 SHA-1: 3ca0492572557827d9213d5e4dd9d47f6e17e78c SHA-256: af9fe0d607f0530fb6e343e48003d1198ed25b8e8d50e9ef12d9b1523cf2d98c
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to other PDFs hosted on compromised websites. The primary goal appears to be directing users to malicious content, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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 https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/3f12f26cc9c3b34f4afe827627fe4e25/zepigubadipojefepitirujos.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160c5856360c54---20699316293.pdf
    • https://grdr.org/paidel/ckfinder/userfiles/files/gupuxego.pdf
    • https://kudamatsu.org/userfiles/file/xutosofumiwina.pdf
    • https://legouic-peinture.fr/userfiles/file/96068462370.pdf
    • http://www.naturhalles.fr/fckeditor/userfiles/file/32309782435.pdf
    • http://shengnabei.com/uploadfile/file///2021062009090038.pdf
    • https://anandamsanyal.com/userfiles/file/dajosadipikiwuwidebus.pdf
    • https://omnistopbollards.com/application/third_party/ckfinder/userfiles/files/6937931752.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607db0b209a4f---21835257688.pdf
    • http://assytekservizi.com/userfiles/files/40427621496.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b46150b2554---furutitikojozuladodaxe.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ae75a3e34---jurenowizusun.pdf
    • https://eownauto.com/uploadpic/files/82354612244.pdf
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/wilugitufokafaxesarakutu.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b57e203fe61.pdf
    • http://camionespanamericana.com/userfiles/file/padite.pdf
    • http://mlkscholarshipsmilwaukee.org/clients/f/f0/f021f13c5c598389be7e913a1ae626ff/File/rodijuvi.pdf
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/r9e85rjf7l6ilq856khend4plo/silawu.pdf
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c916a695a18---92416401641.pdf
    • https://contabil-fiscal.ro/mm/file/69873097966.pdf
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/9bag9qi4iprf4g23dj1usnmk0h/65421189643.pdf
    • https://stpeterscbs.ca/ckfinder/userfiles/files/bewonezoge.pdf
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/553fe6ed239a7629636097c8129fc7f4/35597025208.pdf
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/af05f93365f6c44bbd9dcb0a2d2fc106/xalibemiloniwefutonifexo.pdf
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/917edfb1afa06bf40c4edb60f05969e7/99161209606.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=brock+biology+of+microorganisms+15th+edition+free+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e938.bin
8530d3bde98eb0fbbfa668ec651a8ea682bf41f526cf8c8a4e6512f948114ab3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE938 11652 bytes
font_01_sfnt_off00010483.bin
62a5638e89e71ca4be4d6d936398730195bb588aa89674841f49d6417f1f06e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10483 16796 bytes
font_02_sfnt_off00013029.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13029 16792 bytes