Malicious PDF — malware analysis report

Static analysis result for SHA-256 cea81f33293a5855…

MALICIOUS

PDF

88.4 KB Created: 2021-07-09 23:12:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43aa43d6b679279644492069dc050fb6 SHA-1: 325965f84ba524be7c2aa0c0552d187195f9f96e SHA-256: cea81f33293a5855ed995490905bfd4ce07a33ba2fd09b0fe2a310f2248717e0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as containing a link farm pointing to compromised WordPress uploads and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. The embedded URLs suggest an attempt to redirect users to potentially harmful content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://cructi.ru/uplcv?utm_term=bile+duct+stones+without+gallbladder
    • http://htk2.altrodesign.eu/ckfinder/userfiles/files/fijirojisamew.pdf
    • https://raljob.com/userfiles/file/latilarakaba.pdf
    • http://forter.vn/hinhanh/file/44465819711.pdf
    • http://danies.ru/ckfinder/userfiles/files/51234981430.pdf
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16081dbe0c6477---56988547927.pdf
    • http://canigrup.com/userfiles/file/purixegidisolezekuroso.pdf
    • http://quatanggiabao.com/images/uploads/files/79695328596.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c87c90272e---mipurotujivitiguvetiraje.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bfe6373fac---xitosewofelififekowi.pdf
    • http://zhouzhuank.com/v15/Upload/file/2021630929377745.pdf
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/u6ql92bjusg130agv6kquu3pk0/50730301230.pdf
    • http://saharun.org/uploads/ckfinder/userfiles/files/72844763452.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160a56e9c7fefc---vuwoxiwuwubazeviwepatobob.pdf
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/d73dee137c60cc17ef58d98abf4fc06b/6010451639.pdf
    • http://amandatravel.com/userfiles/file/gokalowaralarefojabeweb.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0fe8be806---63767536790.pdf
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/pitopobiwotig.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/f6616c7e27d4764209529d0c6497053e/sewagozixopago.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/imi4be8gfe23g8t7ar0d8ia0d2/33957848001.pdf
    • https://garraldaarquitectura.com/garralda_userfiles/files/pulibisolofurixufop.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079515d23ac4---mukixovidaxedasokewuminuk.pdf
    • https://movimientofamiliadejesus.com/images/uploaded/file/jevovezubirago.pdf
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/467f64938c87ccecbe582dce0145ecac/97942302036.pdf
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/4af93031c86dcff7f786537544ad390f/zevazuva.pdf
    • http://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/pejanariluguw.pdf
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/ab798de335e21d0384d8abc87f87ddc3/88024830477.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_off0000f6b2.bin
68f486bf5352f26568079ef236af4480d0754a8c97ddd32318664a00f5017c76
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B2 11028 bytes
font_01_sfnt_off00011020.bin
dc96b1a81e1090c47c1486d01c4e4abb64036f2eb29cbbd193fefbb018df18c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11020 16964 bytes
font_02_sfnt_off00013c09.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C09 16792 bytes