Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a7a996844e94011…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 20:55:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1b7890e50a16846113a5637d23c5c586 SHA-1: f40e20e4be1e849abbe13acc743000d962b8cc22 SHA-256: 9a7a996844e94011c0d3f1aaa0cc94da4dc2260698daf097b028521936d40b08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The presence of external URIs and the nature of the heuristics indicate an attempt to lure users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.nvsrolko.org/ckfinder/userfiles/files/44766602616.pdf In PDF document text
    • https://aartipalette.com/userfiles/file/32789857985.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/60249901702.pdfIn PDF document text
    • https://drinkpoint.com/uploads/files/11846714876.pdfIn PDF document text
    • http://domuran.pl/files/file/53997053814.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16144fc51072da---69775901360.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4d455a86b---xunogab.pdfIn PDF document text
    • http://ubest.ru/images/file/60744954361.pdfIn PDF document text
    • http://quangcongluc.com/upload/files/94114244436.pdfIn PDF document text
    • https://ebooksweb.net/files/file/88959278265.pdfIn PDF document text
    • https://magicdiscoradio.com/userfiles/file/86478299038.pdfIn PDF document text
    • http://texmet.pl/userimages/file/xodorurepore.pdfIn PDF document text
    • https://pbpkrosno.com/fckfile/nebali.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/nazezidi.pdfIn PDF document text
    • https://gornjastubica.hr/files/kunagesikuvigovolas.pdfIn PDF document text
    • http://lavalnerina.it/userfiles/file/lakizivinunomo.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/mubidegijukojizetiti.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16132b7eaaf61f---gewodanapiwekakimi.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/97784205892.pdfIn PDF document text
    • http://ciarajewellery.com/editor_upload/file/vugodozeduxu.pdfIn PDF document text
    • http://iccjsc.vn/images/uploads/files/jekonafefufate.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408fee27c93---15957562427.pdfIn PDF document text
    • http://vce34.ru/attachments/file/97678318517.pdfIn PDF document text
    • https://hkfew.org.hk/ckfinder/userfiles/files/34350022932.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=assassin+creed+pirates+mod+apkPDF 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_off0000d900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD900 17100 bytes
SHA-256: 95a99735fd3fa337d279ccc4ffba9bb68ca11aa34ff227d6ddd438ea270ed707
font_01_sfnt_off00010521.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10521 10704 bytes
SHA-256: 2bfa5f716da963e84bf970655f6bb97c82a781fe1fe376d5939703284111f529
font_02_sfnt_off00011db3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1