Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3ed8ebbb11a14e7…

MALICIOUS

PDF

80.1 KB Created: 2021-09-02 20:05:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9bc6fafe4cf31d08e122c66005e0d3e0 SHA-1: 742f759c645c200c994f60b5bbc7f77e58b03ac1 SHA-256: a3ed8ebbb11a14e789576a7438f343d5f0fa42c72bb9b4ded7f3206b1fa1401e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of JavaScript suggests an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160945068e947b---77706704739.pdf
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608b12e58318a---rugeb.pdf
    • https://www.aeap.com.br/ckfinder/userfiles/files/11105946546.pdf
    • https://terminal.hr/userfiles/file/807477259.pdf
    • http://nicenpos.com/userData/board/file/wenogugefig.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b87001b874---loleg.pdf
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acf0c27fa6a---3955823303.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/b523f5a95092553e828a19a0b2b72da6/58603943463.pdf
    • https://kochitaxirental.com/ckfinder/userfiles/files/28022660679.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe0becbf03---48176589435.pdf
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a0eb736f63a---jojokuke.pdf
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/4119201d26efdb76aa8929b957566ef2/62454151007.pdf
    • http://48bulls.com/js/upload/files/tobedajunaxazegojafasip.pdf
    • http://autoscuolapezzano.it/userfiles/files/53487213360.pdf
    • https://masterjobintl.com/ckfinder/userfiles/files/55060606209.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/acd8d5719cde01d59640a56421faf0b9/84103287290.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/fa30560cabe9b6ddf8277431254762be/50955288390.pdf
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/73287a948e669ba90c51932b1fa2a95e/nararas.pdf
    • https://www.axelendinggroup.com/wp-content/plugins/super-forms/uploads/php/files/14bc1d54e1696c19ff2942e45f2fa49c/78099937498.pdf
    • https://harryfok.com/ckfinder/userfiles/files/58187736446.pdf
    • http://cjcounsel.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/60522236559.pdf
    • http://upoart.com/ckfinder/userfiles/files/dizefuvunuxiwifam.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=partial+quotient+division+worksheets+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_off0000d558.bin
fb3dded95b640413835267b61cb72377e603955f4fd2f4876604278139e4a074
pdf-font-stream PDF embedded font (sfnt) at offset 0xD558 11084 bytes
font_01_sfnt_off0000eefb.bin
701d8a64da58e19ba59199d52c46166eff446efe3efe79e92a270d259d1e2c5b
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFB 16928 bytes
font_02_sfnt_off00011a7c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A7C 16792 bytes