Malicious PDF — malware analysis report

Static analysis result for SHA-256 c39b2b164d078558…

MALICIOUS

PDF

91.4 KB Created: 2021-07-14 03:06:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 157698fc0eb00bcdc203a3939e4a2077 SHA-1: fc77b44ae8a4a849c6de60f262850fab6fe4f399 SHA-256: c39b2b164d07855873d1e12e7b9026d6485aad175a2c7d6a057474fa23955b45
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. It also contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://bazis-expertiza.ru/ckfinder/core/connector/php/files/solunudotimumodiri.pdf
    • https://sanvexe.vn/webroot/img/files/loririruj.pdf
    • http://brianhaymore.com/images/e/file/89547658745.pdf
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/7fc40186382beb68eaf790fa05a6ad8e/nepugalesavovibekoga.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbfb5587dd---55843127400.pdf
    • http://astro2sphere.com/admin/images/file/47864582221.pdf
    • http://bobiniauto.com/userfiles/file/39828417532.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16076062a37b34---8875925400.pdf
    • http://capmar.eu/userfiles/file/92880915580.pdf
    • http://albatrossmrn.com/konadnew/userfiles/file/mifip.pdf
    • http://thewellmanteam.com/userfiles/files/45230126743.pdf
    • http://chocoenglish.com/_UploadFile/Images/file/78809699098.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16080a6a70e75a---mojuvus.pdf
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16092bb0cc6261---wizetujulelox.pdf
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079450c2a827---87314030393.pdf
    • http://northmarking.com/userfiles/files/wuwafogafadejijumigufo.pdf
    • http://jingluo.net/uploadfiles/files/jolomawefemubufemotidaja.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/011f8a5f6a5d33a354f811f7b2696662/zatesefitikinuzaniw.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609a040fa988e---papugefafeli.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d44822405a---60297453777.pdf
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/c77d3b74546800de321134d38bc148b6/widugop.pdf
    • http://faithleader.org/js/ckfinder/userfiles/files/xolaja.pdf
    • https://a5productions.com/home/a5pro/public_html/ckfinder/userfiles/files/85525034097.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=history+of+building+materials+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_off00010051.bin
156609ccdead97ef8bad861b060829ef2d2aec6c3b60f96a4473a06d4b3a5eeb
pdf-font-stream PDF embedded font (sfnt) at offset 0x10051 11188 bytes
font_01_sfnt_off00011a12.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A12 16792 bytes
font_02_sfnt_off00013224.bin
d06cb9c41d8945d6f9586680fbaa07f649dfe93a1fe1f79263d97c9c00ff49b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x13224 17044 bytes