Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d78d85e9beb0b9f…

MALICIOUS

PDF

89.6 KB Created: 2021-09-17 09:37:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 89a88864189cac5aa7debfc8aeb56277 SHA-1: eb2944ef20f79cd1c9340cbbd29198af755f833a SHA-256: 5d78d85e9beb0b9f301d5642ce9d83a72c114bc5c5c8d24d57e8dd941adafe0e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated a high probability of maliciousness. The presence of embedded JavaScript and a large number of external URIs, many associated with link farms, strongly suggests a phishing or malware distribution attempt. The malformed stream length heuristic further indicates an attempt to hide malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://drafthe.ru/uplcv?utm_term=modern+magick+pdf PDF link annotation
    • http://www.cenlafilm.com/siteuploads/editorimg/file/95364852030.pdfIn PDF document text
    • http://hotelalbicia.com/userfiles/file/meruzubadabenajel.pdfIn PDF document text
    • http://itfkarnataka.com/cvsprojects/SSK/Source/2.0.0/images/files/80904767556.pdfIn PDF document text
    • http://mijn-nederland.nl/userfiles/file/22489721018.pdfIn PDF document text
    • http://rorolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/supumogofu.pdfIn PDF document text
    • https://kotypsy.pl/ckfinder/userfiles/files/rakenaxovakov.pdfIn PDF document text
    • http://opuspointpartner.com/ckfinder/userfiles/files/42547977742.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131308d131e6---pupufadazedokugofubisafop.pdfIn PDF document text
    • http://advairtech.eu/assets/userfiles/file/wuvepuvugak.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202109131828075538.pdfIn PDF document text
    • http://newshop.jp/archive/file/39811135189.pdfIn PDF document text
    • http://bladensburg.abwingsmd.com/uploads/files/91372234725.pdfIn PDF document text
    • https://sealand-pptc.com/userfiles/file/64826730360.pdfIn PDF document text
    • http://brandweeramsterdamamstellanden.nl/userfiles/file/67795761777.pdfIn PDF document text
    • http://stonepigments.com/userfiles/file/taneb.pdfIn PDF document text
    • http://www.atsamuihaus.com/image/upload/File/49529506831.pdfIn PDF document text
    • http://www.performhabitat.fr/bundles/astadmin/js/ckfinder/userfiles/files/pojisewivadufimirikaz.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/6cc76dec2af41164b1c9341c5849a9d6/misopezivinafabod.pdfIn PDF document text
    • http://maristaslardero.es/userfiles/file/maleme.pdfIn PDF document text
    • http://dissanna.com/temp/fckeditor/file/57905630585.pdfIn PDF document text
    • https://safetypadlocks.eu/eurostyl/photos/file/31713300282.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF973 10736 bytes
SHA-256: 375c7ca677375f8c6f88323099e86bdfbd950f5404e4f273e34ce51ae8ef5fd3
font_01_sfnt_off000111db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000129ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129ED 18360 bytes
SHA-256: 3c29402982f06b465892ca73027f1f76940519aebf9ef7b5394af03a645f3d9c