Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c9b720621a1f84d…

MALICIOUS

PDF

75.7 KB Created: 2021-09-16 21:18:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9eaacf5b21725e5876d03f30c033d8b5 SHA-1: 2c0a066ac1f750629957fc24f38c15b316c1fa1f SHA-256: 5c9b720621a1f84de04893f7428db4c738f626f689d9b437ee24f79c77e6e271
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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 appear to be disposable or low-reputation. This structure suggests a link farm designed to lure users into downloading further malicious content or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://yuli-china.ru/d/files/29367408453.pdf In PDF document text
    • http://unewstoday.com/task/userimages/file/27208453830.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/1041647023.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/84006704238.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/fimofibij.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e2d39c3ce---datazatajigonujokuked.pdfIn PDF document text
    • http://analhospital.net/file/files/madodupi.pdfIn PDF document text
    • http://yavuzselimvakfi.org/resimler/site/files/51192735946.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/71435576490.pdfIn PDF document text
    • http://rlangkhan.com/upload/userfiles/files/77559884523.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/zizisabidirelu.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/wewor.pdfIn PDF document text
    • http://himalayakebab.com/shipinc/userfiles/files/xaduxupuwugubob.pdfIn PDF document text
    • http://les-dvorik.ru/userfiles/file/10415776303.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210901075316.pdfIn PDF document text
    • http://www.patriarca-batiment.com/ressource/site-image/files/gobixotozavaku.pdfIn PDF document text
    • https://khambenhxahoi115.com/images/files/jogavat.pdfIn PDF document text
    • http://turhantur.com/turhantur/files/67410927326.pdfIn PDF document text
    • http://yourmoneyyourbank.com/uploads/File/78285229098.pdfIn PDF document text
    • https://jagamimpi.info/contents/files/zolemixevejedi.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142ab0e505c7---lasoxasuvakajalalusi.pdfIn PDF document text
    • http://f-kcc.jp/user_data/userfiles/files/61140708027.pdfIn PDF document text
    • http://essiac.cz/UserFiles/file/72985743052.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/87331588760.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=best+gbc+emulator+for+androidPDF 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_off0000c331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC331 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB43 17052 bytes
SHA-256: 1f5c6dd2320815df5e9f0b9d692c22f66f558242f051db548fa69da5fbb0f0a4
font_02_sfnt_off00010728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10728 11112 bytes
SHA-256: 4f8d1214810e93813d7dd48e433ee2c190db0e84e088e6fdbfa00bc27089aaa7