Malicious PDF — malware analysis report

Static analysis result for SHA-256 264453c406a3d5c6…

MALICIOUS

PDF

89.4 KB Created: 2021-07-28 12:51:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9e9d4124fa2c5c59939e09a4bbfc0496 SHA-1: 87b7471123dc84b39fb3da6071c2d838070b7de0 SHA-256: 264453c406a3d5c62fbf9768a1597492d4b7b5401fa67363f84b333a12ce6ceb
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. The document body is heavily obfuscated, preventing a detailed analysis of its specific content, but the presence of multiple external links and the heuristic firings are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://cuakeobinhduong.com/upload/files/45697659149.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/1fb6916ed9dde3f55ac607e9cf4ba1df/toredemidone.pdf
    • https://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/65147f06fe61a6c890141822626e1656/37770559895.pdf
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/5937e81c85b89161e15139ec963c613c/80207740886.pdf
    • https://wita.lt/images/files/5138322536.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b78b84ff6---10628141474.pdf
    • http://web68s.com/upload/files/relusalubekeboloso.pdf
    • http://whuntex.ru/userfiles/file/lewiwidoveg.pdf
    • https://fresh-cherries.com/ckfinder/userfiles/files/97749631994.pdf
    • http://deltastal.ru/userfiles/file/xatevapuxazugu.pdf
    • http://hi-techfiber.com/userfiles/file/4186258134.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609034d186501---25355120651.pdf
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/b0e67f1b35505700b53e15f12a1a0721/pagukolojekimilaribudapab.pdf
    • http://alanurturizm.com/rsm/files/74743105111.pdf
    • https://africanresearchcenter.com/userfiles/file/33027115524.pdf
    • http://begemot-rus.com/uploadfiles/file/2021051514285973499.pdf
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/luf59va4afa79ms0raap61nkv0/49599967780.pdf
    • https://vyrukrc.lt/userfiles/file/82997078272.pdf
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2606970a29---tinarozefajawubene.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/7bme74hae8k8cmg5jukkd7a6mo/63304004262.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609841303cd64---56517353210.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbde3a5db83---zokufufelasivikum.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3ssi4hj0jc26dtp02gnjec1af5/kemevotekivo.pdf
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16078fcaa89a3c---zamonabif.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=rowenta+1550w+steamer+cleaning+instructions
    • 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_off0000f6a9.bin
48a8e6afb5e87c09ef011105ede72ef9f78576f43fcb26f8a09083205399f8ab
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A9 11112 bytes
font_01_sfnt_off000110bd.bin
2e491031bc8f31fb78e835510fa8b1fc87a0e3b54eb484f71c319eb8684e9335
pdf-font-stream PDF embedded font (sfnt) at offset 0x110BD 17908 bytes
font_02_sfnt_off00013fea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FEA 16792 bytes