Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b3777f448fd7ee8…

MALICIOUS

PDF

76.5 KB Created: 2021-09-21 21:08:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 775515a5446b309fd8ea033ba9ae1fc6 SHA-1: e58db440265c45e1b791df1b022b0bba59918aef SHA-256: 2b3777f448fd7ee8c0c70f2cfdfba0accda457c7ab5c12628429a4fbd8cb67cf
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to content hosted on compromised CMS upload directories, suggesting an attempt to redirect users to malicious sites. No scripts were extracted, but the PDF structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613afd2bd81da---xiduzanetogudowiziraxilo.pdf
    • https://ajwatravel.com/wheelmarine/userfiles/file/97130384691.pdf
    • https://shian-jin.com/UserFiles/files/mabujuvuma.pdf
    • https://vinniescustoms.com/userfiles/files/64154475798.pdf
    • http://rc-modeller.se/images/file///lutoroxo.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac9d62ef7a---tafozonogilef.pdf
    • http://wirtrauenuns.ch/images/file/97657271180.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/161301877d9ae9---34045139963.pdf
    • https://suativisamsungtaihanoi.net/upload/files/28973214986.pdf
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130e6319da46---dewofegijeteti.pdf
    • https://www.prshots.com/ckfinder/userfiles/files/62540262655.pdf
    • https://kemxoi.vn/app/webroot/files/images/pages/files/58615234059.pdf
    • http://sergeisurzhin.ru/ckfinder/userfiles/files/muzokadabudefuzow.pdf
    • http://greece-ex.com/images/blog/file/juborovoxamu.pdf
    • https://www.uflo.edu.ar/ckfinder/archivos/documentos/fobifetatisenapidefa.pdf
    • http://nattuvaartha.com/assets/ckfinder/core/connector/php/uploads/files/juseto.pdf
    • http://bagiez.de/userfiles/file/jajaxutamulitikenaduluki.pdf
    • http://ipai-bg.eu/img/file/jutawenidifadevawe.pdf
    • http://tuzvedo.hu/elemek/file/duxubamumiwuloxilapa.pdf
    • http://ville-dammarie.com/ckfinder/userfiles/files/6354620900.pdf
    • https://warsztatgdynia.pl/app/webroot/media/files/89003021200.pdf
    • https://soccerauquebec.com/userfiles/file/58642583680.pdf
    • http://litho-and-co.fr/ckeditor/upload/files/kaxel.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=words+that+start+with+a+and+end+with+o
    • http://mustang.tom.ru/jsplugins/ckfinder/userfiles/files/xazefedejeg.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_off0000c7e5.bin
10bb2469aea51c99353ef6929721343332d0c5cabde55d5ea93de8ad858516e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7E5 10380 bytes
font_01_sfnt_off0000df61.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF61 16792 bytes
font_02_sfnt_off0000f773.bin
c99f9c7aa1b23fefd47d711a27d3dac4e77e6c3ab96f6ded05ef5baf9f0e1abb
pdf-font-stream PDF embedded font (sfnt) at offset 0xF773 17184 bytes