Malicious PDF — malware analysis report

Static analysis result for SHA-256 d39f8237cfd2192c…

MALICIOUS

PDF

92.6 KB Created: 2021-09-21 04:22:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0b28837806297aed339d95cece847d0d SHA-1: f070846e1f8bd3b35c3e1dbeb062f400e881dd30 SHA-256: d39f8237cfd2192c3abb397a6965db0c9c273e84f333b9e03c2ce7d78df35130
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised WordPress sites, suggesting a link farm or redirection scheme. The presence of these links and the ML/ClamAV detections strongly suggest the document is designed to lead users to malicious content or exploits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c1225dc82---lowod.pdf In PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/51964649170.pdfIn PDF document text
    • http://sunway.me/ROOT_PATHuploads/file/050919049128.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/zezewabuvijagarabovu.pdfIn PDF document text
    • http://jdjcnc.com/upfolder/e/files/20210911172055.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/161442d1b9a9af---vajesovomimupaxexi.pdfIn PDF document text
    • https://fgcrubochi.com.ng/ckfinder/userfiles/files/sabewuvizawepowozosurirud.pdfIn PDF document text
    • http://nct-vn.com/userfiles/file/42980609342.pdfIn PDF document text
    • http://thrifty-uy.com/files/others/98965606043.pdfIn PDF document text
    • https://silky.ae/images/bulk_images/files/619307520.pdfIn PDF document text
    • http://webminmax.com/userfiles/file/kagotadufilidu.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/jemosokamexujifizewu.pdfIn PDF document text
    • http://klientskazona.radeton.sk/ckfinder/userfiles/files/mafokakibaf.pdfIn PDF document text
    • https://muacash.com/webroot/img/files/6012813136.pdfIn PDF document text
    • http://12shio5.com/contents/files/26763497675.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/3efb629c02c7336f8c45f5e568fb6451/54757863277.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16136f91976d12---38170611325.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/9559200886.pdfIn PDF document text
    • http://arniestribu.com/campannas/file/vaxewe.pdfIn PDF document text
    • http://cesvil.it/filesUploads/file/99019471674.pdfIn PDF document text
    • http://naphotelbangkok.com/userfiles/files/gunufitasuxalogelalasojo.pdfIn PDF document text
    • https://ptogel2.com/contents/files/59662311973.pdfIn PDF document text
    • http://grafosaleservice.cz/images/fck_editor/file/medavufarojutozulap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=sao+alicization+war+of+underworld+part+2+ep+10PDF 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_off0000f87d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001108f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108F 22380 bytes
SHA-256: 35810f33e0c1209ea6431c6368d47c7a01afb1f28df8c69817350bb89a4cdf6a
font_02_sfnt_off00014aa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AA0 11060 bytes
SHA-256: 25585b8c169f841b3b76ef8169ef8cd689ca17db603bc35a833db82b6373a27e