Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce91d61bbb2a99d7…

MALICIOUS

PDF

73.9 KB Created: 2021-07-01 11:21:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 96f05505886cbadc53541a83378c95ed SHA-1: a05185367a00f7811a24f22e31a4a5fca458023e SHA-256: ce91d61bbb2a99d7f59b1ec242ee0531a49a618a0531f03fd94ed6d7965f9f98
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a significant number of external URIs. The heuristics indicate that the PDF acts as a link farm, with many links pointing to compromised WordPress upload storage and disposable hosting. The embedded JavaScript likely facilitates the redirection or further malicious actions. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://irlanc.ru/uplcv?utm_term=ready+first+player
    • http://edumedcare.pl/upload/files/sokanadu.pdf
    • http://ajisushionline.com/uploads/files/moguze.pdf
    • http://shethof.ch/cgi-bin/dynamisch/file/nojulirejifana.pdf
    • https://rosycaffe.com/file/xinifurejozateredi.pdf
    • https://ssvacancy.com/ckfinder/userfiles/files/kaxanukal.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a0ed76b2cea---susoxafik.pdf
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210624120618302944tluru6.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b21fec8e551---mizojumipipevubon.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a6cea091c9a---gaxuzogenowuxobiwulowo.pdf
    • http://akicgiyim.com/userfiles/file/82279949329.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/juwumox.pdf
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/f32f60ff75cb1924d0e9851cb0a065f6/nuworuzedud.pdf
    • http://klubalfa.org/img/userfiles/file/98111348079.pdf
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/nq9fhqqngdv7tm6alvl2r04vuu/5845228212.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160aa8426cb46a---91516275052.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f6062c700---29364608621.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160c9374fb5bb1---faxufoja.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d1dc8744ce---luridejumodomemavagi.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/lm01p7djpm5r1l21kldagvhucd/44878223843.pdf
    • http://ateliergermain.net/sites/default/files/file/57313683748.pdf
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/81518e1e9799cf966dedffffb16d1f39/20513284208.pdf
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/cd0b188edcc4ae0bc72a624d87c8748a/86368369920.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c110820f09f---wubukeb.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_off0000bdc2.bin
b833ea6e8c09538ccf1d0846e10b184ae18806573ca0879e786a0e47feaf4670
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDC2 16668 bytes
font_01_sfnt_off0000e914.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE914 16792 bytes
font_02_sfnt_off0001012b.bin
13a15f18c6de57e9c038cc823fd163a410352b6ae0fe2d0298b8474cae3f1fd0
pdf-font-stream PDF embedded font (sfnt) at offset 0x1012B 10428 bytes