Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc8ddb50d320a69b…

MALICIOUS

PDF

83.1 KB Created: 2021-09-17 15:46:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c342469f1b95043002a39a171281378e SHA-1: 26c480bdf6d0b8bfc5164ba788fd34c9228a7154 SHA-256: fc8ddb50d320a69b960cf8690a9fd00c933f792ca19a5ce3faff92c67b6c2855
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination or spread malicious links. No scripts were extracted, but the overall structure points to a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://xistenze.nagydavid.com/files/files/fofabalafotexotima.pdf In PDF document text
    • https://sinarlangit1.com/contents/files/rajosewave.pdfIn PDF document text
    • http://dainichiji.com/upload_ckr/files/popanomimunarefu.pdfIn PDF document text
    • http://dep14kirov.ru/userfiles/file/wejukuzazafiwopepemaro.pdfIn PDF document text
    • https://indianhairtransplant.com/ckfinder/userfiles/files/31848695702.pdfIn PDF document text
    • http://nmways.com/uploads/fckupload/file/6224131601.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/91916580698.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/b8r88enufjtp4rslt95qbovb04/kemoxomaguvu.pdfIn PDF document text
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/bojemolewugoxadetexigeru.pdfIn PDF document text
    • http://pincodehub.in/userfiles/file/vakoruwoma.pdfIn PDF document text
    • http://spostojow.pl/userfiles/file/zenupusefuzititetaba.pdfIn PDF document text
    • http://lyzebrno.cz/userfiles/file/fomoxotenimoj.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/87557974635.pdfIn PDF document text
    • http://sb-78.ru/files/file/94392948447.pdfIn PDF document text
    • https://la-klamm.org/Files/files/87976378233.pdfIn PDF document text
    • http://belniig.by/public/file/jefukelixakeg.pdfIn PDF document text
    • http://daotaonhaccong.com/uploads/userfiles/file/piperasusavamixid.pdfIn PDF document text
    • http://talani.nl/userfiles/image/file/zakadizesunozelase.pdfIn PDF document text
    • http://connectcontrol.net/files/userfiles/files/lapuzupunir.pdfIn PDF document text
    • https://callmarkinvestments.fortunekenya.com/callmark/files/vemawirovedogona.pdfIn PDF document text
    • http://coquicart.com/ckeditor/ckfinder/core/connector/php/uploads/files/gegugosexisokejakulas.pdfIn PDF document text
    • http://gptools.net/userfiles/file/58652476447.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/91622221847.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=rooted+file+managerPDF 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_off0000de5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE5C 18900 bytes
SHA-256: 95bd5b20206a0362a91f3f51f3142396ca6383917ea7ef32210e142b5dc56118
font_01_sfnt_off00010f1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F1F 10572 bytes
SHA-256: c06c1a66e9fe50196590df1636a65db1cff47d006a204913eae2d2bad45f704c
font_02_sfnt_off000126fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1