Malicious PDF — malware analysis report

Static analysis result for SHA-256 55d39c0a0bae521d…

MALICIOUS

PDF

69.4 KB Created: 2021-10-04 10:16:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 11e0bbc23ce672fea13a07903d9b03ad SHA-1: 68dd2d7f738d9baadf86344ebf242b61c4f85711 SHA-256: 55d39c0a0bae521d68e3546bfbc17ed08c0c87fa6cf3e7fbc18b4e03cb2723e4
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting and appear to be part of a link farm. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the structure and numerous external links suggest an attempt to lure users to malicious sites, consistent with spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 4

  • 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://coretry.ru/uplcv?utm_term=the+sewing+book+alison+smith+free+pdf PDF link annotation
    • http://lt101shop.com/userfiles/files/pedunum.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/85833833728.pdfIn PDF document text
    • http://rungruangsteel.com/public/upload/userfiles/files/18984802146.pdfIn PDF document text
    • http://posicert.com/upload_fck/file/2021-9-22/20210922200106747264.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f70611f5b2---62211431878.pdfIn PDF document text
    • http://gima.ge/admin/ckeditor/ckfinder/userfiles/files/19656037400.pdfIn PDF document text
    • http://7seapharmtech.com/Uploadfiles/files/muxotane.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/33178027915.pdfIn PDF document text
    • https://tukangjp.com/contents/files/moziwujenozudomesuj.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/zuwosiwadafozetedani.pdfIn PDF document text
    • https://bankubezpieczen.pl/userfiles/file/84492997081.pdfIn PDF document text
    • http://ballmillfactory.com/d/files/jogulajumedus.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140af98ae259---xuvasulebugowoze.pdfIn PDF document text
    • http://dwornawodzie.pl/userfiles/file/didexeg.pdfIn PDF document text
    • http://msdoubrava.cz/foto/images/file/naxekukufukiwowowaxijibo.pdfIn PDF document text
    • https://podiummagazinenews.com/ckfinder/userfiles/files/xebet.pdfIn PDF document text
    • https://namphuctourist.com/userfiles/file/92574983646.pdfIn PDF document text
    • http://idcla.net/upload/files/8282979911.pdfIn PDF document text
    • https://naveenent.com/administrator/imagetemp/file/72060478507.pdfIn PDF document text
    • http://starroadchina.com/userfiles/file/6441239876.pdfIn PDF document text
    • http://shipagents.nl/uploadfiles/file/25212747174.pdfIn PDF document text
    • https://brahmagnanam.org/fck_uploads/file/92143522525.pdfIn PDF document text
    • http://sooam.com/files/fckeditor/file/16537268266139c59d04e74.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_off0000b090.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB090 14676 bytes
SHA-256: a24af3d4e8cbfa8e3d754c860fc53e94546c9673c4d605e6e90513f1ffbb97f3
font_01_sfnt_off0000d59c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD59C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000edb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB3 11224 bytes
SHA-256: 14a6de412d7654de2ea0b03383f6f7164d7cc2e41bd7d2047336b697f0393881

Open this report in the interactive analyzer, or submit your own file for analysis.