Malicious PDF — malware analysis report

Static analysis result for SHA-256 496caa21dfc1e268…

MALICIOUS

PDF

75.7 KB Created: 2021-09-02 04:57:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 5c7fdef6f5162956c0ae459b141d4f79 SHA-1: 769c23a6fb7b6abb587b1e07711bf333eafcf5f8 SHA-256: 496caa21dfc1e268e89ae1c436c06d438a5feea1f6f151ba50d459a45457c202
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and embedded links are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://oniceh.ru/uplcv?utm_term=14+questions+in+call+center+interview PDF link annotation
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ac68b5cd40c---77020494073.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/45963235376.pdfIn PDF document text
    • http://remaining-mc.de/userfiles/file/21199627775.pdfIn PDF document text
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160834af2c5f81---96769277369.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/84648680266.pdfIn PDF document text
    • http://cnex.cc/images/blog//file/70967701721.pdfIn PDF document text
    • http://rklatex.com/userfiles/file/najilizetabaliwijijado.pdfIn PDF document text
    • https://cortopolis.ar/userfiles/file/geditad.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160adb8d646b3e---gusobobod.pdfIn PDF document text
    • http://teerosy.com/ipp/images/uploads/files/61991387109.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba7f3f98568---konaferutepezugosav.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/21983430433.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/7863aaabee9dfaaf5369af3bdc967d8a/xobenevix.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/160819adb5bb56---24840234938.pdfIn PDF document text
    • https://www.esfa.bg/root/ckfinder/userfiles/files/96785419574.pdfIn PDF document text
    • http://jongauger.com/userfiles/file/27204045331.pdfIn PDF document text
    • http://quangcaosms.org/media/ftp/file/zapegudojazodi.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/23058626970.pdfIn PDF document text
    • http://nikacarpet.nikacarpet.com/My_Project/Hamishe_bahar/ahar_img/files/bupokogarinedibominuj.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/e8171462d2685b4265764f9c48d287b7/68183327260.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_off0000c76a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC76A 10656 bytes
SHA-256: 378c7bef647dcbdaec7194cad2100d3cba9e663f61eec1b062a1ec60ff1267ba
font_01_sfnt_off0000e00f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f821.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF821 16172 bytes
SHA-256: d28e2f1e000a5ca4e5940d77d1cedb5a5dfa12e6340f112f8c8afa41107e82be