Malicious PDF — malware analysis report

Static analysis result for SHA-256 25d28ec9c4e0f70b…

MALICIOUS

PDF

88.8 KB Created: 2021-06-25 14:29:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 1810374ee874c4a3ec782902660eab63 SHA-1: 93e706d1062ef5442a107b8956d4ef8084ff1398 SHA-256: 25d28ec9c4e0f70b04d678272935fc35131c9e83e0d1dbd3c4719c2732a1f06c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://horizontire.com/userfiles/file/jowonotalugozufupedira.pdf In PDF document text
    • http://pantryscan.com/123cars/imagefck/file/palasajenamoto.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/1ea3b1d71f8fdac7cee4864361a370db/domizi.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a53daf9136f---4945614524.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/34198309698.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/1eckf69k8obgcdj1p2k4hnfmho/numojewufa.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/20674182522.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0ed9ea129---54256213463.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d51924784db---kanevojifuw.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/8enb84jqjghn098ph1s9qe0an8/33545778823.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f8149e825a4330b0f0fc22c31ce67d55/34546552296.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/1a725f193be239247c8c841d40e77e2c/88257618872.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/fadenuriju.pdfIn PDF document text
    • http://planbmedia.hu/files/tojavaluduvi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=automatic+control+systems+10th+edition+solution+manual+pdfPDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad9cdd092ce---45119735786.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_off0000f431.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF431 11256 bytes
SHA-256: 51e167c6f84c97ba6f32624894cefcccd3d482ede6b026c196bcf755763857cd
font_01_sfnt_off00010e76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E76 17432 bytes
SHA-256: 12dcd5449f532222bb7cbcfd10019d0faf90957219324835facbd20c9773121c
font_02_sfnt_off00013c53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1