Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9322600a66ef1ae…

MALICIOUS

PDF

69.9 KB Created: 2021-09-27 09:06:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 479cb1d8f32baef9da5745f1d9fe1278 SHA-1: 6829110d7e69613674303531ace020f71168dae0 SHA-256: c9322600a66ef1ae6dede10c35ae8be64190bee383e9cff63497af75b4f987a7
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to other PDF files hosted on a variety of domains, many of which are unknown or suspicious. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a deliberate attempt to create a large number of links on disposable hosting, suggesting a campaign to distribute malicious content or phish for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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 http://zhongyuemedia.com/filespath/files/20210911192408.pdf In PDF document text
    • http://bogaarchitetti.it/userfiles/files/sozedugitila.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614cd190cf8b5---lolepuvomubofewabun.pdfIn PDF document text
    • https://dp-silver.com/userfiles/file/mumapiw.pdfIn PDF document text
    • https://bozoklar.org/ckfinder/userfiles/files/viturezugoji.pdfIn PDF document text
    • https://am-system.eu/ckfinder/userfiles/files/7492592647.pdfIn PDF document text
    • https://daiichitravel.com/uploads/news_file/sipazafupu.pdfIn PDF document text
    • http://tropo-design.com/ckfinder/userfiles/files/rexuperabuvid.pdfIn PDF document text
    • http://27derajat.com/assets/ckfinder/core/connector/php/uploads/files/samadodulotunetolo.pdfIn PDF document text
    • http://mcutech.net/files/vozof.pdfIn PDF document text
    • http://euro520.net/userfiles/file/1630588653402424267.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/ladunusileganamajab.pdfIn PDF document text
    • http://banquat.com/userfiles/files/nevirakativagozu.pdfIn PDF document text
    • https://dunaweb.co/bg_image/files/25729028536.pdfIn PDF document text
    • https://franciscovalles.comtraining.cl/userfiles/files/85696772817.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/11797235232.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/lawofetevilefom.pdfIn PDF document text
    • http://capthepcongtrinh.com/uploads/news/files/3169093459.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/wekugegumimarufef.pdfIn PDF document text
    • http://innotack.com/userfiles/files/41222286690.pdfIn PDF document text
    • http://shop-cartuning.pl/userfiles/file/zirurisumerelafizox.pdfIn PDF document text
    • https://www.miotsukushi.or.jp/system/ckfinder/userfiles/files/11497655562.pdfIn PDF document text
    • http://hostingureitings.lv/uploads/userfiles/files/gupufejabilibejokuronuj.pdfIn PDF document text
    • http://qdsenfeng.com/data/files/89822936173.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=android+volume+booster+that+actually+worksPDF 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_off0000b278.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB278 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA8F 11216 bytes
SHA-256: ef662a32189c037a6026109dd33536bb3bd91e0e6fb9d6668d33dbbe491e7773
font_02_sfnt_off0000e4bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4BB 14680 bytes
SHA-256: 73fd5f35416306f386adb7318e9a6d2625e87c82a382ff5a4875c6db0d359419