Malicious PDF — malware analysis report

Static analysis result for SHA-256 2de0b4d85e0233cb…

MALICIOUS

PDF

85.7 KB Created: 2021-07-18 20:21:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 40847d44eeb92a40a16e29d0be726170 SHA-1: 25df413689ed6327c92d66d19cc9d4f7fdbc08d9 SHA-256: 2de0b4d85e0233cb4e1a27b15b36537bf4489fbeb7b473f34943f3bda34d715a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS upload directories or are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links. The embedded JavaScript is likely used to obfuscate or directly facilitate the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://esterkins.de/ckfinder/userfiles/files/98594783216.pdf
    • http://tlxzkj.com/uploads/file/090642327498.pdf
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/piv75k0vcr746b8j4g7hvl2f7v/bobaxoziginugisuxolam.pdf
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/2e7ef79d1da33b9282ded1814c82ccc2/97365673470.pdf
    • http://firanywiktoria.pl/uploads/editor/file/kijoxetafinidofilawodet.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aa9549b47c---duruxamaramadik.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160994ceb78c5a---76673156147.pdf
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/17f10584bbeb73f951dd8592fd3d0451/86154005513.pdf
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/dunawidesese.pdf
    • http://www.aadhar-interior.com/userfiles/file/96551850306.pdf
    • https://alixdemassy.fr/userfiles/file/fixovepumemuxakefijaxo.pdf
    • https://birotex.rs/images/files/22741208878.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1c082a32fa---fikoxivikukedazefo.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/f91512c281d6803cb43f4aa177654c2d/gatesunulevijemotopojog.pdf
    • https://veaodaibrahma.com/uploads/image/files/ladokin.pdf
    • http://www.lebedosapartotel.com/data/yukle/files/repafeginasukit.pdf
    • http://ekolojikweb.net/upld/userfiles/file/70399991839.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abadc94107e---domojosasemuwutebadigaz.pdf
    • https://atl-50.com/files/file/90197906854.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9cb224140---67064191267.pdf
    • http://autoshiftbid.com/fckeditor/userfiles/file/rezovoloroxir.pdf
    • https://abugfreemind.com/userfiles/file/50794092923.pdf
    • http://alexanderjamesbackcatalogue.com/userfiles/file/82451581577.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f0d3e1c1f2d---34540981137.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=colin+clark+and+marilyn+monroe
    • 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_off0000ecff.bin
96d96a0b49edc67326a19195c3a771e5ddf3b11e9d7534ddb5bfb1bc6bb180e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xECFF 17092 bytes
font_01_sfnt_off0001194f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1194F 16792 bytes
font_02_sfnt_off00013166.bin
9357090af6deec26ca0f4db621850240880254a882ec8be36657040600d1804e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13166 10500 bytes