Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f888ae4b76b31ae…

MALICIOUS

PDF

79.2 KB Created: 2021-09-19 20:48:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 57303692692bd7f003532dda166bc76b SHA-1: 1205bcf632cb28c3ae0243b765d1761dab4447d2 SHA-256: 6f888ae4b76b31aec663cb437049304964ed3a0f762d13580f9c4e8f46a82f30
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous embedded URLs pointing to external domains, many of which appear to be part of a link farm designed to obscure the ultimate destination. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically calls out the structure as a non-clustered link farm on disposable hosting, suggesting a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://smidgel.ru/uplcv?utm_term=aimer+conjugation+french PDF link annotation
    • https://medicabg.com/uploads/wysiwyg/files/podarulojeb.pdfIn PDF document text
    • http://vom-ragnaroek.de/uploads/file/zuruduwejuwixele.pdfIn PDF document text
    • http://bona-agra.pl/Upload/file/40550602410.pdfIn PDF document text
    • https://hamayeshniroo.com/shop/file/davubebukajawubetovewam.pdfIn PDF document text
    • http://abnicum.ru/files/file/59845191624.pdfIn PDF document text
    • http://auswallendorf.de/userfiles/file/9808186367.pdfIn PDF document text
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/xuvuwulizebumise.pdfIn PDF document text
    • http://robbes.nl/media/files/junobamagazaka.pdfIn PDF document text
    • http://domario.ru/userfiles/file/xevolid.pdfIn PDF document text
    • https://vonia.mikludava.lt/images/files/1837673433.pdfIn PDF document text
    • https://trsoftyazilim.com/genelresimler/file/52137120518.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/75730079254.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/gisutebubivog.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/10708452339.pdfIn PDF document text
    • http://fijiembajak.com/uploads/ck_uploads/files/57470166275.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c16b1bb395---98396111860.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/1819588340.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/63553614406.pdfIn PDF document text
    • https://kawanmto.com/contents/files/52284305463.pdfIn PDF document text
    • http://www.blueoak.fr/image/file/miloxegemadewuwoloxolem.pdfIn PDF document text
    • https://plewmal-d.com/Uploads/files/56210458844.pdfIn PDF document text
    • http://connect-event.fr/ckfinder/userfiles/files/rokusi.pdfIn PDF document text
    • https://villadelauca.com/userfiles/file/35066545269.pdfIn PDF document text
    • http://gesgo.de/userfiles/file/lafegemapudubifipufa.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_off0000d0bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e8d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8D2 10780 bytes
SHA-256: 4808565d21ffe6e4fa9cd7075f9b69bbc8d3c9779f73d3fc9ac44da795116443
font_02_sfnt_off0001016a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1016A 17620 bytes
SHA-256: 13fbee9acd327661096d801fabe42f10419faa862d8067101d0bdf2ee3056e30