Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5353a4b67afb8a2…

MALICIOUS

PDF

82.0 KB Created: 2021-09-09 06:26:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b838fbd74f4ea76def9f6989b1b04e1f SHA-1: 378f51fda140f737e40bab1366c8cdfdbe11882c SHA-256: b5353a4b67afb8a2b259f8e6872550043c8f8ad493fe0b0175e9dcaa24bbc8fb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links and the overall structure indicate an attempt to lure users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://tgroupsrl.com/userfiles/files/52398512269.pdf In PDF document text
    • https://wisestudentz.com/userfiles/file/jefusa.pdfIn PDF document text
    • http://studiovalecchi.it/userfiles/files/69008118097.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/16553441908.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/fapowe.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/mabufuxozojire.pdfIn PDF document text
    • http://telecycling.info/files/file/30399814899.pdfIn PDF document text
    • http://maturitni-ples.eu/UserFiles/File/timuvapaxuvakuzabaped.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/115855310.pdfIn PDF document text
    • http://chrisdepanneservices.com/Sites/cds/files/84314391860.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/d5c9cc46706bdcb4ba284e2b6cb4d062/fagigesax.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/90492350316.pdfIn PDF document text
    • http://argyleliquidations.com/userfiles/files/93534753168.pdfIn PDF document text
    • https://penzion-palice.cz/content/98772962098.pdfIn PDF document text
    • http://tnslib.su/userfiles/files/15225956120.pdfIn PDF document text
    • http://getwealthythisyear.com/ckfinder/userfiles/files/71693440733.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/161303e907f944---98811536245.pdfIn PDF document text
    • https://ritascreation.com/userfiles/file/23004211012.pdfIn PDF document text
    • https://mashtalkandil.com/userfiles/file/juzolira.pdfIn PDF document text
    • https://csmgh.net/pevron/www/img/file/rarezirubasupoxogimeju.pdfIn PDF document text
    • http://dpnovelty.com/upload/files/fokexageda.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b9fbb8a44---vorozuwareg.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/4943707993.pdfIn PDF document text
    • http://gniortho.com/files/Upload/file/49882288605.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=apk+street+fighter+2+champion+editionPDF 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_off0000d9ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9EE 11216 bytes
SHA-256: a47cf613df7966cd3014c7bc3fd44eb71218afde08574686b441f081dcf6900c
font_01_sfnt_off0000f3f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C05 17584 bytes
SHA-256: 3b5e2e87998cce7449558d165d337ac0ad4fbd8b9499e704c80398b0368a60c5