Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5f2ee9762499f4b…

MALICIOUS

PDF

80.5 KB Created: 2021-09-11 18:02:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5538d564fe89e96fe25937b76523441f SHA-1: 251d627a9a9d1237c802a430b2b7c60f711357bd SHA-256: c5f2ee9762499f4b04a2975e3481d37f865c7efe5dd72c5a0e7e1f0b60fdac3b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://synerhu.ru/uplcv?utm_term=redmi+y3+new+update+miui+12 PDF link annotation
    • http://p-jtech.com/userData/board/file/2141565862.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/cb646a2ac3cdede514fa8700faee3325/90854063299.pdfIn PDF document text
    • https://tradingphrases.com/userfiles/files/xiletezokemu.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16134783daf048---notigoxuzodo.pdfIn PDF document text
    • http://www.ocptecnology.com/admin/uploaded/fck/file/86962931168.pdfIn PDF document text
    • http://sooclose.eu/upload/File/11314353507.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/63002565121.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/75569375617.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/kulalefisewamex.pdfIn PDF document text
    • http://xn--80aafjbawrcdgsodbdciig4a5v.xn--p1ai/pict/file/89982151285.pdfIn PDF document text
    • http://xn--76-6kca8aqc6c.xn--p1ai/pic/userfile/13854328169.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/31024319131.pdfIn PDF document text
    • https://yourownadviser.com/ckfinder/userfiles/files/lexututixirow.pdfIn PDF document text
    • https://multimetrics.com/ckfinder/userfiles/files/56287922484.pdfIn PDF document text
    • http://graviroz.hu/ckfinder/userfiles/files/14777763410.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/wasixobumizitawede.pdfIn PDF document text
    • http://jcnjl.com/userfiles/files/tosonezavo.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/cf6a83f3d4976bedab069f3e51f907ed/pobewurimologiwowot.pdfIn PDF document text
    • https://sanruouvang.net/images/uploaded/file/90261615553.pdfIn PDF document text
    • http://perlawarmii.pl/userfiles/file/dozabofusulomexapigixumub.pdfIn PDF document text
    • http://baltyk.recykling-rejs.pl/imgturysta/files/gutasosifus.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613203e9f00a8---31128068386.pdfIn PDF document text
    • https://filetorme.com/upload/files/42059373583.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_off0000d522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD522 17860 bytes
SHA-256: 9219eaeb7dc6aa0c76a455a2445b5d0c8407417dc1ffb3d38dd6cd69f01f0d58
font_01_sfnt_off00010354.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10354 10808 bytes
SHA-256: a7dfdf94f7a856b3e28dec484c4a99395e39cf29cb3b3898a637f5ac95bb6b35
font_02_sfnt_off00011c6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C6B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1