Malicious PDF — malware analysis report

Static analysis result for SHA-256 24086c568f9766a5…

MALICIOUS

PDF

84.1 KB Created: 2021-09-07 17:56:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0447c243ce6e8de1eb77cced374a9c51 SHA-1: 7a9a85ab28d9c6fdea2fb11da8b6cf6970410665 SHA-256: 24086c568f9766a5afe7fc8a18b2d9149877ea82ae473ad4e22d24488556a31f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it's part of a link farm hosted on compromised WordPress sites and disposable domains. The embedded URLs, such as 'https://allytemp.ru/uplcv?utm_term=biopsicologia+john+pinel+pdf+descargar+gratis', are likely used to redirect users to phishing or malware download pages. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious documents designed to exploit users via social engineering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 https://allytemp.ru/uplcv?utm_term=biopsicologia+john+pinel+pdf+descargar+gratis PDF link annotation
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbf5bc8bf1---fewarofon.pdfIn PDF document text
    • https://cahayaapi1.com/contents//files/27562356456.pdfIn PDF document text
    • http://randalljroutson.com/clients/44711/File/refojinazidoveturez.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/87c901e0c2b4b08cba2a429ebdded05f/66984727119.pdfIn PDF document text
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0797a2287---64414139789.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/hurc4pu2oql2airqtqdjve0ito/26267391457.pdfIn PDF document text
    • http://aktifbant.com/resimler/files/gefaxurizo.pdfIn PDF document text
    • http://yourbuilding.ru/userfiles/files/zomiwo.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160831e70b1bd6---nugivuvugamabupinivemonav.pdfIn PDF document text
    • http://espicycooking.com/files/file///vilojijitojuzenef.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/2dc9de47818960c0d39f9f662f8d3cef/43962163974.pdfIn PDF document text
    • https://securitegenerale.tn/userfiles/file/boroxuzede.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1607aac18532ab---71749742667.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/a8102126693cbea20cfe8260ee7543de/64754432916.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/depozifuromijimusofawu.pdfIn PDF document text
    • http://natpuedu.in/userfiles/file/86823157145.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/buvunozuxazefuxibiruro.pdfIn PDF document text
    • http://planao.com/ckfinder/userfiles/files/35132966651.pdfIn PDF document text
    • https://codecs.ro/images/file/sewipojumilulutogapozo.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609fd5383e33b---kojavetasugix.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/setowilav.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f6fb50c34d3---genepunitanodobixufog.pdfIn PDF document text
    • http://abpaluso.com/upload/file/18079148397.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/kubil.pdfIn PDF document text
    • https://najlepsze-w-polsce.pl/uploads/kijimeneximisotu.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/fojupu.pdfIn PDF document text
    • http://guitarenko.fr/img/files/dozudebibazezudu.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f9d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9D2 11080 bytes
SHA-256: a6a336c9dd1899efa2dd8dc76443cec5d61b6baea8d733fcc21ff8d7faae22a5
font_02_sfnt_off00011367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11367 18516 bytes
SHA-256: 1de9a819188ede68147c0693a9f22804fff64735ef7f0c4062c0ad835f6fdfb4