Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4fb259127e7062e…

MALICIOUS

PDF

79.8 KB Created: 2021-07-08 13:05:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 786944d28c52d661699b13a30bd12d76 SHA-1: f986c0cfe280b9ae67e3703b4e9b7bd995c90a90 SHA-256: f4fb259127e7062ed7455ec59c32f1520710ba831d0e6639962b8fc3e40a320c
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and unreadable, but the presence of numerous external URIs and the link farm structure indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://teplospectr.ru/images/files/40084788177.pdf
    • https://betenenergy.com/sites/default/files/file/witigedetaniwenigeroluj.pdf
    • http://circuitvietnamcambodge.com/hinhanh/file/75807529150.pdf
    • http://aire-limpio.com/img/editor/file/62448729869.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d78785867c3---xepaboredidos.pdf
    • https://skspiti.com/userfiles/files/61865136780.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606c93df53429---42029912808.pdf
    • http://likebarcode.com/image/files/20210705_134730.pdf
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/410548a414ff54f32c6165fdfbcd5933/wutoxonuwalefiwul.pdf
    • https://esperanzadeavila.com/fotos/file/51609503829.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/9bb816e959417fac8b4235f7cafb85dc/bogojabazatela.pdf
    • http://bualuang101.com/backoffice/upload/files/72639370715.pdf
    • https://liniagdanskzydowo.pl/files/meferob.pdf
    • http://mini-garden.ru/userfiles/file/93882504245.pdf
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609faa93f0e72---54976071690.pdf
    • http://botosani.ro/img/uploads/file/wurevo.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc25aa0bec---gamareguretas.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072cb85097c2---vugip.pdf
    • http://teplospectr.ru/images/files/puxumovosidugamux.pdf
    • http://t-p-fortune.com/userfiles/file/54110365798.pdf
    • http://jatyn.cn/upfiles/202106/file/1624122805.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc80dde56c---4874784139.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607e37287944e---zeregezimaxo.pdf
    • http://flexa.cz/docs/file/boxedopewodunozudelonoda.pdf
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/e7b94f0f07f99cab453d82c9a9dc2e8b/66381693156.pdf
    • http://www.annaleehuber.com/content_files/file/2402605498.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=chess+opening+fried+liver
    • 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_off0000d352.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD352 16792 bytes
font_01_sfnt_off0000eb64.bin
e124881725145b1ab8aed54278bdefee0db37c4de3b3ef76b8ee993fb53ec811
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB64 17040 bytes
font_02_sfnt_off00011841.bin
01a2c33b72adca97c46b8b80b1e996bccb3dcd38b92cde9b6a715787a428f29f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11841 10616 bytes