Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea968f4fb37dd1d4…

MALICIOUS

PDF

86.3 KB Created: 2021-07-02 12:49:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a9a13e5c7bbfe7ffdd35f7e236ce2a06 SHA-1: e79b7b1c6eee5fb37ae023b8a365eaed39f084d0 SHA-256: ea968f4fb37dd1d4d2a948868811f50a7519c6dbda11437e1053188d4b58d479
164 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to execute malicious code or redirect users. The PDF also functions as a link farm, pointing to numerous URLs hosted on compromised WordPress sites and other disposable domains, suggesting an attempt to obscure the final malicious destination and evade detection. The primary purpose appears to be directing users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b28b824f8---takeba.pdf
    • https://brahmagnanam.org/fck_uploads/file/19785173125.pdf
    • https://equator-maritime.com/userfiles/file/zamorenovawe.pdf
    • https://ktmcollege.org/public_html/userfiles/file/pifejevawidus.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d67027ec80---54727228633.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a76afa3a47---mimalufeduwugivido.pdf
    • http://netpost.vn/upload/userfiles/files/nodixoxinezopevuta.pdf
    • http://rszm88.com/upfolder/e/files/20210626105248.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/v8cva24chb5g0d5e7ldpgvva50/buxexexufonijowodetowepa.pdf
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/9eaa628696c320dae1a3ede5ce160820/40562620549.pdf
    • http://amy-tsai.com/images_express/userfiles/files/kotuzimedufeji.pdf
    • https://ystechpro.com/nbloom/fckuploads/file/18629045683.pdf
    • https://kimtuong.vn/isc/public/files/fckupload/file/gepinunadavefovaladip.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608259e7d855f---gafagopuba.pdf
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/8dbcf2d0b98e6963df04b081523e0fad/33493365179.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16083efbd64ad9---4270849026.pdf
    • http://carnow.jp/js/upload/files/14764560154.pdf
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/bop3t0u15no6usmihd3ufit5bg/baxalusaxotat.pdf
    • http://conblocmanado.com/pics/file/rajatebijaxa.pdf
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080d5ed4f629---rizajaxirurarobupazugeba.pdf
    • http://baloneacessorios.com/_upload/file///8104378576.pdf
    • https://munord.com/wp-content/plugins/super-forms/uploads/php/files/24b86fcf22e4f9e24c25ccc4ba7fa69d/pelifujalewifekepeg.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=how+long+does+barley+last+in+the+fridge
    • 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_off0000efae.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFAE 16792 bytes
font_01_sfnt_off000107c5.bin
d96b9c3d4a10bc8d6265700a9d61fd26940c3358daee50f4499bcf81407584af
pdf-font-stream PDF embedded font (sfnt) at offset 0x107C5 10964 bytes
font_02_sfnt_off000120f6.bin
40a635272e4018a062c70495055a789a74d6de3d540c8d12e1265f4c3fc687fd
pdf-font-stream PDF embedded font (sfnt) at offset 0x120F6 16636 bytes