Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa6f7d077508774…

MALICIOUS

PDF

83.6 KB Created: 2021-06-29 20:53:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e497d922adff66da75825f26c2b22e47 SHA-1: 31ccdcb94c36f8a0ae43465fc37da6ac625b5ede SHA-256: caa6f7d077508774bf9c5080f0c7cd86bcfc8f96e187da89c757286335fc35f1
204 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous links to external PDFs hosted on various websites, many of which appear to be part of a link farm. The heuristic 'SE_BROWSER_INSTALL_LURE' indicates the document likely prompts the user to install a browser extension or update. This, combined with the ML classifier and ClamAV detection, strongly suggests a malicious intent to trick users into downloading further malware or providing credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160930d15a23b3---79998821847.pdf
    • http://alexlunacoach.com/img/editor/file/golul.pdf
    • http://manleyboone.com/clients/3/3d/3dd19be848c73b0ce3a0430f7fd535f3/File/23354693726.pdf
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/20592026928.pdf
    • http://longbienco.com/js/ckfinder/userfiles/files/gulopelununanefejofisej.pdf
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160764fa4c976d---94735953187.pdf
    • http://hysansam.com/fckeditor/userfiles/image/50746463262.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/fc9475284db24f28cef91f62fbf34bfa/dafojed.pdf
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/53754307703.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada9c24dcef---debobexuzamix.pdf
    • http://www.anclupnapoli.it/userfiles/file/mofax.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c00576bb621---dipozopawewudi.pdf
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a002fc4329f---44962740146.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/d434ebfd544410e305754fbd50fb6678/relefofuzisunijo.pdf
    • https://marljivo.hr/userfiles/file/58184383125.pdf
    • https://delphin-restaurant.com/ckfinder/upload/files/gikogubomuwe.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d31150ce26---siresomizidevosap.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5ec1634f5---67721250775.pdf
    • https://uleshuzataruhaz.hu/files/file/74545885150.pdf
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/0rmfdlsbohc5hat415mruhch91/sonowes.pdf
    • http://drairtools.com/ckfinder/userfiles/files/33517278472.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=install+chrome+os+on+any+laptop
    • 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_off0000e388.bin
66615d5580eb5b17d1dca75fb128b1c0fe1bf2a5d8250e0d93f545e523e21165
pdf-font-stream PDF embedded font (sfnt) at offset 0xE388 10612 bytes
font_01_sfnt_off0000fba9.bin
05c92c353f0b3a5486b087bf2cbedf1daa0d67f1f9a53ffd464bb1f0dc3395bd
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA9 16912 bytes
font_02_sfnt_off000127a2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127A2 16792 bytes