Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bf7a57cc3230172…

MALICIOUS

PDF

94.6 KB Created: 2021-09-17 15:52:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 5f0f58bb010bf24fdfce1311dab3c632 SHA-1: e617ff00aaa4570d69610ecee1a7d652d79430ad SHA-256: 7bf7a57cc32301724071b3d0cf70eff658329fe52f58125def64ef1fb0c25b3b
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics, including a critical ClamAV detection and a high ML classifier score, indicating malicious intent. The presence of embedded JavaScript (PDF_JS) suggests an attempt to execute code, likely to redirect the user to malicious external sites as indicated by the numerous PDF_URI and EMBEDDED_URL findings. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the phishing or malware distribution nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://cukimentescukraszda.hu/files/files/mezade.pdf In PDF document text
    • http://chatyzvule.cz/uploads/duzera.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1631514040.pdfIn PDF document text
    • https://soudureornementalelauziere.com/upload/editor/file/zuropejopobe.pdfIn PDF document text
    • http://synphabase.ch/upload/file/47550778349.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/puminepidunemovuputu.pdfIn PDF document text
    • http://sushrutproctology.org/ckfinder/userfiles/files/pedumabojinijogujim.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/1613b09371cba3---rinenitojitirokorajigugiv.pdfIn PDF document text
    • http://aaas.handyfriendship.com/upload/files/laposexugonemitupa.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/5040832294.pdfIn PDF document text
    • http://zs-g.jp/app/webroot/js/ckfinder/userfiles/files/49185702106.pdfIn PDF document text
    • http://support-cmu.com/filedata/file/zidolekepoviwuxoramujif.pdfIn PDF document text
    • http://stisk.com/file/wefipifagadezik.pdfIn PDF document text
    • http://czytamzezrozumieniem.pl/userfiles/file/3035529350.pdfIn PDF document text
    • http://kcpsystem.com/userData/board/file/91010771337.pdfIn PDF document text
    • https://poganyvolgyi.hu/userfiles/file/70964090398.pdfIn PDF document text
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jitevatafutere.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/rajovuletep.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/de7vka9d19ftepjtveqtkt3g8i/84035833518.pdfIn PDF document text
    • http://yamamatoen-wanwan.jp/ckfinder/userfiles/files/13808988174.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=cookie+clicker+shadow+achievementsPDF link annotation
    • 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_off00010289.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10289 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011a9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A9B 21868 bytes
SHA-256: ee38e9be61dc778e3a3b1e906a9df297c9631c0670afbd9141e987a53b181146
font_02_sfnt_off00015377.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15377 10908 bytes
SHA-256: b6075f1eb7b5c520b051f3cdd128fcd5f6d379167f08c93a4f561205fad8e450