Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbf731ab3fd1fd6a…

MALICIOUS

PDF

86.0 KB Created: 2021-07-31 13:13:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7c1f2a6f97ee80b3afd1b196bfe13931 SHA-1: c3bd0c58f7267b8e2fa4f884056cf52dadf56311 SHA-256: fbf731ab3fd1fd6a1503d0410a2cbe3a9671546bcf74585b0f8a08b0daf56c37
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of links, many pointing to compromised CMS upload directories, suggesting it functions as a link farm. The primary purpose appears to be directing users to external, potentially malicious, content rather than containing a direct exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://aisef.org/uploads/userfiles/file/file/pojoxekipodomaxon.pdf
    • http://nappsa.org/userfiles/file/47559096848.pdf
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/5d69a71ff03f7b447edce7f81b258075/95615449391.pdf
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1ecbb014a5---watojewuwaji.pdf
    • https://hirurgija.me//files/15736650135.pdf
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/nosmn3lb7cdgjpgs3rqi30b5hp/tativudupijak.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1bf6c9f435---kugabiza.pdf
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/4jdv8uaip7a0j3ks5gsela13t2/zerofix.pdf
    • https://bhalakusari.com/uploaded/ckeditors/files/sevizobopubafavugat.pdf
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609892308c5f8---85947384818.pdf
    • http://turinhotelcompany.com/userfiles/files/53721322872.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/ee061767bfc8b9cd8be4e6572f1396d4/vituxexeduzosaruloda.pdf
    • http://archerelectricsupply.com/userfiles/file/37570405317.pdf
    • http://ronaldtan.nl/images/photo/pepizeguzapefowixo.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088d5e754959---41582192607.pdf
    • http://www.kilincsweb.hu/fileok/file/likisape.pdf
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7114282f53---rediboj.pdf
    • http://stauarchitetti.eu/userfiles/files/pudunejenofaj.pdf
    • https://stvorki.ru/files/file/diborovotiwunabemoxitedu.pdf
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/fotoguzovo.pdf
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b42ee1db18---11495905733.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=what+is+the+oxidation+number+for+group+3
    • 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_off0000e9b0.bin
9802a05e03dc12f5473966a285608febae4f1d81b533996d86d870b46176c900
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B0 11404 bytes
font_01_sfnt_off0001040b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1040B 16792 bytes
font_02_sfnt_off00011c1d.bin
fcc0d277e79a216048787e721966ff1202bf276d0349aa2d46c0ba3c053f379d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C1D 17356 bytes