Malicious PDF — malware analysis report

Static analysis result for SHA-256 cad91ce7a5af07e1…

MALICIOUS

PDF

78.8 KB Created: 2021-09-11 14:35:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 94131cc7c03fee05680169e1819f5d6f SHA-1: 5050abb33f251daa8c76a0272e46d112426ada14 SHA-256: cad91ce7a5af07e1cb47c6992b74dafd50d2eff561a4aa5ba9b9baabe2d28db5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/ec22542f65c0c34a4ede28a439edf5cc/83700304424.pdf In PDF document text
    • https://bursakaynak.net/userfiles/file/43153452710.pdfIn PDF document text
    • https://shriramsteels.in/public/ckfinder/userfiles/files/1728292328.pdfIn PDF document text
    • http://moscowfashion.net/content/xuploadimages/file/13663204517.pdfIn PDF document text
    • https://www.kindspring.org/inc/ckfinder/userfiles/files/46659318003.pdfIn PDF document text
    • http://stainless-faucet.com/uploads/htmlupload/files/dixonowizavobo.pdfIn PDF document text
    • http://armiikrajowej36.pl/public/upload/ckfinder/userfiles/files/93848616368.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcdf61c3c3---76375881635.pdfIn PDF document text
    • https://inprovitvenezuela.com/ckfinder/userfiles/files/97036813965.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/98956801653.pdfIn PDF document text
    • https://angkalaris.com/contents/files/63457798954.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130f586df15b---vonokebikagorasimasa.pdfIn PDF document text
    • http://s-privod.ru/userfiles/file/44829015648.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16135ced3d750b---34603834830.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/41709515053.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/52556030532.pdfIn PDF document text
    • http://spadhotel.com/basefile/spadhotelcom/files/tovari.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/jukif.pdfIn PDF document text
    • http://reliancefla.com/admin/images/file/79579210181.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/wutuvikalogufegiwugiw.pdfIn PDF document text
    • https://magnanerie-cazilhac.com/userfiles/file/80476238172.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=how+to+use+a+custom+live+wallpaperPDF 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_off0000ccec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCEC 18772 bytes
SHA-256: 499c6e025c084bec6941a9b605feaeb99fa623b93fdcb6d279389932ef626c14
font_01_sfnt_off0000fd42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD42 10672 bytes
SHA-256: 1b6dc5915c277fa1d082ad0f07ec591e3de01dad689fba89609bc76a1d22c01f
font_02_sfnt_off000115ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1