Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8b9d1cf2428a62d…

MALICIOUS

PDF

84.7 KB Created: 2021-06-27 12:12:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 06b32bdb650af8f96107232be82639ce SHA-1: c10d829d069726207b5f1eb1c58430fbf21bb5f3 SHA-256: f8b9d1cf2428a62d56027127c11679af1b0ed03d04ccd30416b4b9c2c0d15ba1
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to websites hosted on compromised CMS platforms or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure as a link farm suggests an attempt to lure users to malicious sites, aligning with spearphishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://infrive.ru/uplcv?utm_term=how+to+make+stable+doors+for+horses+minecraft
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160ba4784bfb24---xubedodumijod.pdf
    • https://hrmconsulting.biz/upload/files/fugajafegagufap.pdf
    • http://files.ibiza-ferien.de/file/fibavoxovulak.pdf
    • http://cuatudongsaigon.vn/uploads/files/96954065524.pdf
    • http://www.cafeinca.com/img/public/contenido/file/55157329474.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/f8837bd901ef39c3096dac4507647115/31896009784.pdf
    • http://kawoka.com/userfiles/file/8048456386.pdf
    • http://jnnycc.org/userfiles/file/2775962326.pdf
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/e2d03f62b98bfd805b64d399357c9645/52969037372.pdf
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fafce18e97---kibezozumeti.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d93c760ab2---27403358007.pdf
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160aba9fd7c154---43509736673.pdf
    • http://austria-ex.com/images/blog//file/tosujelomigepi.pdf
    • http://webinaris.biz/ckfinder/userfiles/publics/files/78718304532.pdf
    • http://tvkinter.com/file_media/file_image/file/11214185340.pdf
    • https://wfca-czech.cz/temp/userfiles/files/45660494089.pdf
    • http://kondicionery-lubertsy.ru/upload_picture/file/rivopejenuniwakam.pdf
    • http://hopkins1983.com/clients/861771/File/52120683543.pdf
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/b90db3c4c8c1152b04011de69bd590a7/fekutugupevitim.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160703e40d54cf---15417483855.pdf
    • http://alrabbancapital.com/file/files/19490390069.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160948719bfece---jimer.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/9cc800ee74ca7d542c976f6ee75cd023/rotekobejowavuluk.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072aacb2ed44---88030532510.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_off0000e7c8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C8 16792 bytes
font_01_sfnt_off0000ffdf.bin
f3f060c24014d0dd1c243b205b69f9f74a9052edcb0e82ec104764b28ad832d0
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFDF 11052 bytes
font_02_sfnt_off00011968.bin
b725db0ee51f3c4d1507b0772ecb4cf52a530b6783e0dc1af786d61d7100166d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11968 16996 bytes