Malicious PDF — malware analysis report

Static analysis result for SHA-256 fda156f82ddcfff2…

MALICIOUS

PDF

78.6 KB Created: 2021-09-18 12:19:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4c5a2cc34f019b627eb5db7156b217c5 SHA-1: 0ecb0fcf13d49956fb49dff8d5cb15525204d020 SHA-256: fda156f82ddcfff245f7d0057f36468b6e603ae8b85283e1730b4dbdaec7c983
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute traffic. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple external URIs suggests an attempt to redirect users to potentially harmful content. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • 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 http://gsprojekt.eu/userfiles/files/97913147140.pdf In PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b8f32848b---wekazenajevapudabugezom.pdfIn PDF document text
    • http://aczelzalog.hu/tmp/54032044868.pdfIn PDF document text
    • http://silarperu.com/UserFiles/file/sesakewivowijidez.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/f1d9e47fdca7f99623c8112f567aa7b8/fujovofusa.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/528aa0cbfc658d369e5459bd44db9edc/nuwikibagaja.pdfIn PDF document text
    • https://maggievanostrand.com/uploads/media/file/28898251118.pdfIn PDF document text
    • https://winpoasia.com/ckfinder/userfiles/files/topupadizalazogilimul.pdfIn PDF document text
    • https://bosingels.nl/ckfinder/userfiles/files/29689674654.pdfIn PDF document text
    • http://e-pisanie-prac.pl/famprojekt_z_serwera/images/file/42962235643.pdfIn PDF document text
    • http://studiocastigli.eu/userfiles/files/xuxutojivewesuwazukeni.pdfIn PDF document text
    • http://chengzechem.com/upload/files/29066623120.pdfIn PDF document text
    • https://elemonbg.com/Files/File/55950509996.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/69065399768.pdfIn PDF document text
    • https://duel.pl/userfiles/file/9501990740.pdfIn PDF document text
    • http://apismorava.eu/docs/10031357592.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/68297339121.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/5c4c26d1ea1fae021ff6827edf00c93f/patupenujid.pdfIn PDF document text
    • http://bivalyracing.hu/files/file/golomuxonasewaloge.pdfIn PDF document text
    • http://getem.pl/files/file/nurotuwuru.pdfIn PDF document text
    • http://ipublicity.cz/data/file/runuxowax.pdfIn PDF document text
    • http://club-integra.ru/userfiles/file/pegenupar.pdfIn PDF document text
    • https://cherrychile.cl/cherry/uploads/contenido/files/31232190714.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/nuxoxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=a+whole+new+world+piano+sheet+music+musescorePDF 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_off0000cf3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF3B 17216 bytes
SHA-256: abaf00c8cda7b05984e5004866d9faf2b423d7ca89ad565865f737c19fcd2a96
font_01_sfnt_off0000fb68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB68 10944 bytes
SHA-256: 0cd873d52bfce88c1ea64a5e5a47357bedbc767c567e1ba28121ebd2a036ecb7
font_02_sfnt_off000114ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1