Malicious PDF — malware analysis report

Static analysis result for SHA-256 87a283ddbc726bdd…

MALICIOUS

PDF

82.5 KB Created: 2021-09-12 22:31:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1c87e3c69f8999bbdd6ec42d4fc6c232 SHA-1: 2b6c213d4cca5a890a7dde56470be97793d1f936 SHA-256: 87a283ddbc726bdd62654a85672a002914c9220b447522777e9fad1c12f420a9
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains embedded JavaScript and numerous external URIs, many of which point to other PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The presence of embedded JavaScript and the nature of the URLs point towards a phishing or malware distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • 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://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a6abb51726---52814974477.pdf In PDF document text
    • http://cetis156.neutronds.com/assets/js/ckfinder/userfiles/files/vimasuzesoperivefoziwupo.pdfIn PDF document text
    • https://gencshoworganizasyon.com/upload/ckfinder/files/mutexitasokakixim.pdfIn PDF document text
    • http://ilsogno-bomboniere.com/userfiles/files/47515026558.pdfIn PDF document text
    • http://mptech.vn/ckfinder/userfiles/files/51011732297.pdfIn PDF document text
    • https://pasarangroup1.com/contents/files/28066657545.pdfIn PDF document text
    • https://www.opsclown.it/ckfinder/userfiles/files/69168896713.pdfIn PDF document text
    • https://genegurumiraclehealer.com/userfiles/file/65072194998.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/61053181523.pdfIn PDF document text
    • http://www.bluewhaleline.com/image/upload/File/80328698981.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/kupuvusabu.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/tusolesatezipudim.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/7rb2sp9lbp2emj73e10gnsf5ha/28323693081.pdfIn PDF document text
    • http://budgettranslation.hu/sites/default/files/file/kusif.pdfIn PDF document text
    • http://fsgzb.com/upfolder/e/files/20210902120449.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/6425119499.pdfIn PDF document text
    • http://ntep2008.com/UserFiles/File/44437359941.pdfIn PDF document text
    • http://hiroi-es.info/yamituki-n/uploads/files/mesogilomatejelokegepiwos.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/lebajipunezorujogo.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/80862778848.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/12900623336.pdfIn PDF document text
    • http://xetaihyundai.net/upload/files/norexupagoxuwovaxuv.pdfIn PDF document text
    • https://masihpt2.com/contents/files/rimekew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=arc+welder+apk+download+for+pcPDF link annotation
    • https://easyown.ddproperty.com/datas/files/30231146342.pdfIn PDF document text
    • 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_off0000da92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA92 10412 bytes
SHA-256: e4e77f651f88aef0a69c11d961134ed45d47b2cf038501a9ee8873290aa9e9df
font_01_sfnt_off0000f251.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF251 19444 bytes
SHA-256: 1bc2d3809a5a8b8f4c6546010e962165ad485a647af2ad9b411d037c17be9181
font_02_sfnt_off000124c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1