Malicious PDF — malware analysis report

Static analysis result for SHA-256 cde3f584fc4b74ba…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 20:45:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 07955888576486249d6b2c2d0233dd2e SHA-1: 23bd2d4ca3033abf12cfe3d1554feebe478afcd9 SHA-256: cde3f584fc4b74bacb56ff39b1f8a75142e7eabd6e6640baf656f2f558b326ad
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or distribute content across many domains. No scripts were extracted, but the overall structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://redac.ch/upload/gogidekezexufuratilu.pdf In PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/95116255093.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/89199199226.pdfIn PDF document text
    • https://arerp.kr/data/file///9222867566.pdfIn PDF document text
    • http://tecresconsolidamentorestauro.it/fck_data/file/gebawuvu.pdfIn PDF document text
    • http://leasingtowers.com/ckfinder/userfiles/files/39781613116.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/val4fkbtil6fqu2gao5gp1o51g/87028173119.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/54709168419.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/35983840886.pdfIn PDF document text
    • https://pragatitic.org/ckfinder/userfiles/files/nopirejupuze.pdfIn PDF document text
    • http://agriturismolataggiasca.eu/userfiles/files/dakodojubasu.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332ce159fd2---42451989139.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/giremewebatukizow.pdfIn PDF document text
    • http://pr-jam.com/ckfinder/userfiles/files/69219872955.pdfIn PDF document text
    • http://restavratorstvo.com/ckfinder/userfiles/files/fimibapevegofidamupezimam.pdfIn PDF document text
    • https://kozhikodedeaf.org/admin/my_files/file/kovimimudotebuvenuli.pdfIn PDF document text
    • http://ebbers-schilderwerken.nl/uploads/files/lopukafiwewod.pdfIn PDF document text
    • http://musicpark-live.com/userfiles/file/jaguwevopiwiwofaz.pdfIn PDF document text
    • http://asremajazi.com/uploads/files/67559119901.pdfIn PDF document text
    • http://taxfreepoint.com/file/63584359534.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/kojaduretegunig.pdfIn PDF document text
    • https://kaowei.tw/image/files/20210902_133140.pdfIn PDF document text
    • https://cleartunemonitors.com/ckfinder/userfiles/files/zudewiwoni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=top+5+strongest+economies+in+the+worldPDF 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_off0000d68d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD68D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eea4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA4 10980 bytes
SHA-256: a0ef0479a87483a3530d86db2774e5cc9d5724372eb626029e62ba8685fb9a4c
font_02_sfnt_off000107d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D1 17676 bytes
SHA-256: 313ed52e5f46a0b63d3ea44e84520e1e54efdca069b5be5c524e14c1f83c6499