Malicious PDF — malware analysis report

Static analysis result for SHA-256 b516b0625248584f…

MALICIOUS

PDF

77.7 KB Created: 2021-09-13 15:31:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 79108504c7b558e4bd3bd8c39a52bb5a SHA-1: cd2c85cc6e8ec824afb95b3d6e125ad442f3688a SHA-256: b516b0625248584f749e9c564e98a4c6a6c7182c5aa2abdb95fae8468b4d5af1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9829

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://crysiq.ru/uplcv?utm_term=minecraft+apk+caves+and+cliffs PDF link annotation
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/94406742020.pdfIn PDF document text
    • http://elisa5888.com/shopadmin/upload/files/rilasomovavagi.pdfIn PDF document text
    • https://kaemsp.org/upload/editor/file/96320819976.pdfIn PDF document text
    • http://www.stsmcc.org/www/js/ckfinder/userfiles/files/vijowidoxumumujonuwuwu.pdfIn PDF document text
    • http://floramarble.com/uploads/kazat.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/41072789054.pdfIn PDF document text
    • http://osayit.com/images/file/nekakewegawonazitiputaba.pdfIn PDF document text
    • https://stpatswatertown.org/ckfinder/userfiles/files/53433213831.pdfIn PDF document text
    • http://winhazel.com/indigo/ckfinder/userfiles/files/jefixo.pdfIn PDF document text
    • http://sostrevalli.it/userfiles/files/48391036865.pdfIn PDF document text
    • http://keifo.ru/ckfinder/userfiles/files/sadewikunugefuworuj.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/wafasupa.pdfIn PDF document text
    • http://costruzionibulagna.it/userfiles/files/58050473845.pdfIn PDF document text
    • http://kleinschadenexperte.com/userfiles/file/jonozodajebegurapo.pdfIn PDF document text
    • https://barcelonacentromedico.es/files/galeria/files/temibimuporeloz.pdfIn PDF document text
    • http://e2ingenieros.com/ckfinder/userfiles/files/rijavezabamav.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613b97feb67cc---kivobagijiledugut.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161350c310098e---82330988826.pdfIn PDF document text
    • http://choragwica.pl/userfiles/file/gibipanutuxoxigevufopaw.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/10844044977.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/76629791210.pdfIn PDF document text
    • http://sherwoodchambergolf.org/ckfinder/userfiles/files/liket.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/56685650567.pdfIn PDF document text
    • http://dsraxys.com/uploads/wopokezadinonodonaferukup.pdfIn PDF document text
    • http://www.espaciocultivarte.com/ckfinder/userfiles/files/37198791987.pdfIn PDF document text
    • http://www.zaluziemalina.cz/userfiles/file/kojijosurimel.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_off0000cbd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBD6 10644 bytes
SHA-256: 400fcf3f9c5bd96fc9e4fe342b2582f797a642821f046ffab51505b2f18b8e76
font_01_sfnt_off0000e457.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE457 17560 bytes
SHA-256: 956792039e4cfe146351623b356ae4f8fadab1f1ecaf34fe845d8942e7c35893
font_02_sfnt_off00011170.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11170 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1