Malicious PDF — malware analysis report

Static analysis result for SHA-256 a29b0ed69b2bd1ca…

MALICIOUS

PDF

86.2 KB Created: 2021-09-18 03:36:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a0b2b6be76e976a026206281ffb1e9eb SHA-1: 1ae75432b7d8d6e243947217192ccc55f46e448c SHA-256: a29b0ed69b2bd1cada7c686e168658eb4e8c6a8f0705920abb15101d352a369d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. The heuristics indicate the PDF acts as a link farm, pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to obscure the true destination and evade detection. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • 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.
  • 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://to-tuong.com/media/ckfinder/files/fojek.pdf
    • http://cupta.org/userfiles/files/20210905011227.pdf
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/46904825473.pdf
    • http://ellissi.org/userfiles/files/95620982461.pdf
    • http://churchtextile.com/userfiles/file/dudanukiwamokofixinig.pdf
    • http://opt-russtd.ru/data_center/upload_pictures/file/44518711796.pdf
    • https://castilloexterior.es/ckfinder/userfiles/files/wexuxejevasikovopotabawi.pdf
    • https://bunexim.dascalita.ro/app/webroot/files/userfiles/files/rubotefevekevobirebowag.pdf
    • http://voijin.com/userfiles/files/kapebivavojaxum.pdf
    • https://yam-token.com/business_school/uploads/file/gebeligavovuzuwewabej.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140388c53cfe---96881191709.pdf
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/rsj2e7ic2dc5pvgao7tmsiveli/bukewa.pdf
    • http://sns.hu/_user/file/93596374053.pdf
    • http://nutronicltd.com/userfiles/file/82040953812.pdf
    • https://mingyi-lock.com/data/file/userfiles/files/93862422708.pdf
    • http://garage-ys.info/js/upload/files/15990733109.pdf
    • http://studioriggio.it/userfiles/files/xilexigelirujilug.pdf
    • https://adsbudget.net/userfiles/file/8114239273.pdf
    • https://angel-juicer.com/FileData/ckfinder/files/20210916_58FF09EA8B3578A6.pdf
    • https://edusfera.pl/upload/file/91667038217.pdf
    • http://zeamailer.zeapost.com/FCKeditor/editor/filemanager/connectors/userfiles/file/43026691553.pdf
    • http://grandioso.asia/editor_upload_image/file/basafi.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/c1ef2086e860b302f3e02d810fb5c8e5/27177129582.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/89a1j9e4g849ccd48kj3fp499u/79536377480.pdf
    • https://www.adom.biz.pl/ckfinder/userfiles/files/luwifafusobojapigigodorix.pdf
    • http://shopphutungmayphat.com/upload/img/files/27904148073.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=entertainment+apps+for+android
    • 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_off0000ed2e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED2E 16792 bytes
font_01_sfnt_off00010540.bin
e829fa8756a0beea40168c18878eb1190ac916425fa1dc23faf3b8f2318ea550
pdf-font-stream PDF embedded font (sfnt) at offset 0x10540 17504 bytes
font_02_sfnt_off000132a6.bin
3fb84e016d1e091b738520f68af2f261bd74468d26af58bf6f5bf910660c2e99
pdf-font-stream PDF embedded font (sfnt) at offset 0x132A6 10596 bytes