Malicious PDF — malware analysis report

Static analysis result for SHA-256 b0b237dac8a8d74d…

MALICIOUS

PDF

75.9 KB Created: 2021-09-17 11:03:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 28ff72744694669a83bd51f87c47174e SHA-1: 3c3a6c608209da513e21db9d6eb9611c8e5943ff SHA-256: b0b237dac8a8d74d4e716217c5cded4f15cf9e12ee6a720db6f33e6c0dec7fb7
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external PDF files hosted on disposable domains, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the presence of numerous external links and the PDF structure point towards a downloader or phishing lure, likely using embedded JavaScript to facilitate the redirection or payload download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://ed-web.cz/userfilesfile/6765224983.pdf In PDF document text
    • http://premo.at/userfiles/file/87231042601.pdfIn PDF document text
    • https://villatoscana-pi.it/userfiles/file/xarudataw.pdfIn PDF document text
    • https://manualismedicina.hu/fileok/file/80074237586.pdfIn PDF document text
    • http://csc0731.com/userfiles/file/20210916235820_7pmguc.pdfIn PDF document text
    • http://carraracucinecomponibilitrapani.it/userfiles/files/56489567450.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613b333b0db2d---xoreritanazelog.pdfIn PDF document text
    • https://betamachinery.sa/other_files/File/pomamutewe.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/vapamufufoleluparubepem.pdfIn PDF document text
    • http://studiolauramoschini.it/userfiles/files/guwovisenigasofe.pdfIn PDF document text
    • http://weforyou.it/userfiles/files/74313259559.pdfIn PDF document text
    • http://refpecsbelvaros.hu/kepek/files/nusinetisu.pdfIn PDF document text
    • https://csam-villepinte.org/uploads/images/file/nazug.pdfIn PDF document text
    • http://izeninfo.net/admin/upload/files/vaweboj.pdfIn PDF document text
    • http://cherryontop.pl/upload/fotki/file/jofagilidokixokozu.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/67800593201.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/74503338243.pdfIn PDF document text
    • https://houstoncoinclub.org/FCKeditor/file/jokivafesikipomiz.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613a22e50af06---sotepoxudufe.pdfIn PDF document text
    • https://onsale.social-push.cc/data/fckeditor/files/xedajavetididuvev.pdfIn PDF document text
    • https://textmakareknutsson.se/upload/image/42651116947.pdfIn PDF document text
    • https://sweetburden.com/upload/users/files/629464215.pdfIn PDF document text
    • http://igs.compcierge-asia.com/ckfinder/userfiles/files/jasareseduvovuxabazonup.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/najawenutup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=download+second+class+citizen+pdfPDF 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_off0000c3d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3D2 17432 bytes
SHA-256: a39bc3117d4bb17f460fa9901797337102affa749d50e43352139dba9f2a35a8
font_01_sfnt_off0000f139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF139 10660 bytes
SHA-256: 821e3d0f62ad02335cb1b624c52f5a2025371cd8fee53c850d1d42d95304e705
font_02_sfnt_off000109d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1