Malicious PDF — malware analysis report

Static analysis result for SHA-256 8760f8ba9352cf97…

MALICIOUS

PDF

97.4 KB Created: 2021-06-27 19:16:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aa26a9e938169833494de57d75a4be2d SHA-1: e142d4f86f733f97f6553d3571ec76cdef6f9599 SHA-256: 8760f8ba9352cf97c87ea24c7a2b8a561b2e9087ea69152bf70b4eed9cb76392
156 Risk Score

Malware Insights

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

The PDF was identified as malicious by a ML classifier and ClamAV, flagging it as a phishing trojan. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and contains no readable text, indicating it is not intended for user interaction but rather as a vehicle for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://theatresaucinema.fr/uploads/file/91607820907.pdf
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c484e86b900---4035151789.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a074b3477---sozinalunaseniserujun.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/456463e219c7afd2cf8e3bd12d58747b/tivuzud.pdf
    • http://vce34.ru/attachments/file/35892828799.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/5ed5584a93a0f6d99a890fa506a72714/xuxexobawijemezovetunofum.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/90712065759.pdf
    • https://jagominum.com/contents//files/44882981775.pdf
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/op6v6fh33rivph1gafk9bqvc40/gudaluvuwumuwapajiwitotus.pdf
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2d00e6751---39957070137.pdf
    • http://drairtools.com/ckfinder/userfiles/files/19263744080.pdf
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/gijuzigozo.pdf
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aba3304e57f---54892063142.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16081b6ecc65da---88362839535.pdf
    • https://aadhaarretail.com/administrator/imagetemp/file/91899415453.pdf
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/55hvm4lbe67d5a11g9cqdisl3j/tudafetigol.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160743bde69cfc---jisedukigasipixolozud.pdf
    • http://omgmediatank.com/userfiles/files/kitejixotegawilu.pdf
    • http://brmhn.com/userfiles/file/20210523204554_pi4e5u.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160a638ffe7ee1---87842862498.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c725e3cc7a---kewamijaxevavagilu.pdf
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/4qmr4g6s1smqo422hjenune3ag/40077028402.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=categories+of+dogs+with+images
    • 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_off00011b37.bin
582f8e934720ea5928db36f572dafa9cfb2a446f00670296fa357f975cf97118
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B37 17152 bytes
font_01_sfnt_off000147a6.bin
255c7a671e98f8d37eb0de87ddeea29d3cef9bd55b79ab0d8a52c53a2bce8475
pdf-font-stream PDF embedded font (sfnt) at offset 0x147A6 10768 bytes
font_02_sfnt_off00016057.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16057 16792 bytes