Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad34accc81916fe6…

MALICIOUS

PDF

80.6 KB Created: 2021-09-15 21:08:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1704baf1e1f2e2530833289d06a41d25 SHA-1: a01254071eeaf25c059a403caf3b6135c900e68d SHA-256: ad34accc81916fe6b44f35bcc58ee03747918235cb52906cf88e7fe489d9f93f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. The presence of numerous embedded URLs, many pointing to disposable hosting and employing UTM parameters, strongly suggests a phishing or malware distribution campaign. While no scripts were explicitly extracted, the PDF structure and embedded links are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://ketchas.ru/uplcv?utm_term=city+island+mod+apk+unlimited+money+and+gold PDF link annotation
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16130bda051fae---50718048110.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/kotuxuvawizokenulaferu.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/xesozenikelexezadozip.pdfIn PDF document text
    • https://triptoboloyfoundation.org/editorsfiles/files/vodutu.pdfIn PDF document text
    • http://kozszemle.hu/uploads/files/jukowavikenato.pdfIn PDF document text
    • http://mobilenmr.com/files/files/46672566932.pdfIn PDF document text
    • https://kuni.ro/app/webroot/files/userfiles/files/3197088934.pdfIn PDF document text
    • http://synerfreight.com/syner_upload/images/files/98350057346.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/falezabotatapedagixunuwa.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/45752065977.pdfIn PDF document text
    • http://etyekilovarda.hu/userfiles/file/lezemomigorevoluwafukubud.pdfIn PDF document text
    • http://hyunsin.net/userfiles/file/kimijekuforuzen.pdfIn PDF document text
    • http://acevina.com/webroot/img/files/lupik.pdfIn PDF document text
    • http://pengyou-english.com/FileData/ckfinder/files/20210915_218C3F470E52A94E.pdfIn PDF document text
    • http://syntrend.critical.tw/upload/files/gasuvudajexojod.pdfIn PDF document text
    • https://zlato-eu.cz/upload/files/bimukiluzuporutexinozi.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/tizule.pdfIn PDF document text
    • http://motivationandmomentum.net/ci/userfiles/files/18374656288.pdfIn PDF document text
    • https://luatsubienhoa.com/upload/ck/files/zawedivopo.pdfIn PDF document text
    • http://valsadindustries.com/userfiles/file/45865367095.pdfIn PDF document text
    • http://dbexpertise.fr/catalogue_dynamique/file/66768587886.pdfIn PDF document text
    • http://upakuika.com/img/file/42464103230.pdfIn PDF document text
    • https://ganganagardentist.com/userfiles/file/joxafubalenama.pdfIn PDF document text
    • http://mybyblos.com/userfiles/file/tivoliferamusira.pdfIn PDF document text
    • http://robfredo.com/userfiles/file/figuzaxorazetibogumevuli.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_off0000d667.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD667 17292 bytes
SHA-256: f9cb270bc948fe8566649a56d78473004a16d0ad9a91a2b9daccf90922404120
font_01_sfnt_off0001031a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1031A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B31 10972 bytes
SHA-256: 8dc8667e6e2b796a0ac4b85f5b2c77af78dc351f38e347e34005254547a1c4ee