Malicious PDF — malware analysis report

Static analysis result for SHA-256 b21163b4043f4bed…

MALICIOUS

PDF

81.7 KB Created: 2021-09-23 09:37:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ad26c1afda637911d5986cb226f3b955 SHA-1: 02f21fd063d299b32d465ca0c16865942ff70964 SHA-256: b21163b4043f4bede7a07acdd39ca63e344cc724490569a41f9d2ac3e7899aed
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple domains, many of which are hosted on compromised CMS upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites. The presence of numerous unknown URLs suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/fhbu5p642r34a3m3onl6pknod3/67708640660.pdf In PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/92399908403.pdfIn PDF document text
    • http://naso10.com/userData/board/file/43004820607.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/3b94008aca440e1209df7ab404e8398b/30098974463.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/53589576939.pdfIn PDF document text
    • http://sofia-es.tokyo/yamituki-n/uploads/files/zonudutavunaxopojevavob.pdfIn PDF document text
    • http://studiogaleazzo.eu/userfiles/files/97854227619.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/11113500296.pdfIn PDF document text
    • https://shen-su.eu/gfx/userfiles/files/74738201599.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/wafakur.pdfIn PDF document text
    • https://preciseenergygroup.com/media/bokez.pdfIn PDF document text
    • https://nvsrolko.org/ckfinder/userfiles/files/77707842215.pdfIn PDF document text
    • http://thy-environment.com/userfiles/files/ripiwokanet.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202109/file/tilekajixuganon.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/sekekapugixowop.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/43506292730.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/kaxujavukapiwevutiwub.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a209c03462---16854109680.pdfIn PDF document text
    • https://bbpartner.cz/userfiles/file/puxakuwiwesasizowep.pdfIn PDF document text
    • http://e-menu.hu/editor_up/66053957417.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/kexiwajorozepufadatavo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=samurai+vs+zombies+defense+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_off0000d4da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4DA 11048 bytes
SHA-256: 6082fb8eb2fa7a066f5b7a8f319afc7b9d0c28f0605e6183823d7f56521e504e
font_01_sfnt_off0000ee5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010670.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10670 19572 bytes
SHA-256: 010a72dadbe817a4195b61a74988d8e6a967f19634ad84bab48a6d02e45500b5