Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4055864957098bd…

MALICIOUS

PDF

90.0 KB Created: 2021-09-22 14:27:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e7a52fee8afc007aec5f1b0d4c33fbde SHA-1: f013d0c9865f2cf0f8acfe608a86c3bffde6351a SHA-256: c4055864957098bd90157d104cd76bbc6b2654cf50631f52f7e402f9fdf8ddad
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites and disposable hosting. These links form a link farm, suggesting an attempt to distribute malicious files or redirect users to phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • 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.
  • 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://garglob.ru/uplcv?utm_term=descargar+aplicaciones+para+android+en+tarjeta+sd
    • https://luxesystem.site/js/ckfinder/userfiles/files/nopevifuwuvomerulafera.pdf
    • http://ebus.cn/up_file/file/zoril.pdf
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/8002956190.pdf
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/ca580df25afedba13fc0b19dba48c27e/37636317889.pdf
    • http://medwin.kr/userData/board/file/sezuweponasov.pdf
    • http://nowator-zpu.pl/userfiles/file/28700884415.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f742c22546---64425578585.pdf
    • http://thietbinuoitom.vn/uploads/userfiles/file/zitujiwodiwiduvapogo.pdf
    • http://garage-ys.info/js/upload/files/defezokazitok.pdf
    • http://poornasreehomeoclinic.com/ckfinder/userfiles/files/76838687437.pdf
    • http://www.examnotice.in/uploads/files/60469126250.pdf
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614712f2073a6---lufilov.pdf
    • http://lncxjzxxw.com/upload_fck/file/2021-9-20/20210920192447253108.pdf
    • https://sca-eagleegg5k.com/ckfinder/triplebuserfiles/file/97958193744.pdf
    • https://trsoftyazilim.com/genelresimler/file/65612651910.pdf
    • http://sanxuatbanthinghiem.org/app/webroot/uploads/files/45439841324.pdf
    • http://araulmor.tel-cor.com/images/library/file/zipugemebepavox.pdf
    • http://studioagronomoserragiotto.eu/userfiles/files/rukapawekogekemoxekuwuna.pdf
    • http://doxetrilinh.com/media/ftp/file/surikadoripupiga.pdf
    • https://thibiditrading.com/public/userupload/files/78789885490.pdf
    • http://npas.ru/pic/file/bigefapagafabekologe.pdf
    • http://edmo-cars.nl/images/file/81163782884.pdf
    • http://logtech.cz/foto/Image/file/28903351889.pdf
    • http://ros-grad.ru/fck_editor_files/files/lutip.pdf
    • 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_off0000f409.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF409 16792 bytes
font_01_sfnt_off00010c1b.bin
6cf72c78356d4a350ae8527438439ba325dc5c8334bf22fd41f08c9bd9756689
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C1B 20204 bytes
font_02_sfnt_off00013fc3.bin
e77d255348ba4a45fdb78dd43f81c8c4f08b21fb3ff9a850ec66d204b08c8f87
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FC3 10820 bytes