Malicious PDF — malware analysis report

Static analysis result for SHA-256 38d454583efe0c25…

MALICIOUS

PDF

69.9 KB Created: 2021-09-25 06:20:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4e6f79509cd7dee9062a012e7af0b603 SHA-1: c02a2eb2526906cadff71d36ebdda300e76c8e99 SHA-256: 38d454583efe0c25a24360fbbd5a6367cfe17f4ffb08c5e64b0ccff94d5fb978
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or SEO poisoning campaign. Although no scripts were extracted, the presence of numerous external links and the nature of the heuristics strongly suggest the document is designed to redirect users to malicious sites, potentially for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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.
  • 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://xyoaa.org/sites/default/files/files/35303144270.pdf In PDF document text
    • https://zlatartopalovic.rs/files/wilevonevev.pdfIn PDF document text
    • http://bsp-oblspl.org/ckfinder/userfiles/files/15192109563.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/14048192529.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/tekavozikikokewikolim.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161322921b65f0---morel.pdfIn PDF document text
    • https://buka.ru/sadm_files/39413089549.pdfIn PDF document text
    • http://entrackintl.com/uploads/90560265288.pdfIn PDF document text
    • https://mimzyonline.com/userfiles/file/89927520855.pdfIn PDF document text
    • http://xn--b1amishc2fb.xn--p1ai/ckfinder/userfiles/files/zilalufu.pdfIn PDF document text
    • http://artospace.com/pics/file/51108688313.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b867e26efe---kexurunelu.pdfIn PDF document text
    • https://vargyasnekonyveles.hu/kepek/other/file/mozunejupajo.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16136d2ce7f78a---58571353048.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/25543043993.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614522a7daea8---dugoxu.pdfIn PDF document text
    • http://wuxihemei.com/ckfinder/userfiles/files/20210923_181155.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/3068522054.pdfIn PDF document text
    • https://tepatsasaran.com/contents/files/22740029121.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/gexujafatipukiran.pdfIn PDF document text
    • http://ibrahimalsada.com/pics/file/92090964217.pdfIn PDF document text
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/73393296704.pdfIn PDF document text
    • http://uk-finansist.ru/userfiles/file/zikesobi.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/5c682d4c91128d6c64a36a090e5a5650/vojudozeje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=m51+android+11+updatePDF 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_off0000b302.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB302 15248 bytes
SHA-256: e16c5043eced49cc94c1fe5db55675e31a1a8477e496c91d6a1ee82b8e2330f7
font_01_sfnt_off0000d9e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FF 10448 bytes
SHA-256: af9ff69a3af5360e1a44eaa5dfcc869d3f2ca7fed6e4be2c20c9381717102588