Malicious PDF — malware analysis report

Static analysis result for SHA-256 b381729d5acb3ee0…

MALICIOUS

PDF

84.0 KB Created: 2021-09-24 11:33:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9aeba42ec5661fc33b34168bee4302f6 SHA-1: 0b1fad3b1fa022d8424d26ef9359ceac89a5ca1a SHA-256: b381729d5acb3ee0c03cb9eb9621cb1a1fc36e5ad42a92de1af237f0e5361604
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the URLs and the PDF structure suggest it may leverage embedded JavaScript for malicious redirection or exploitation.

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 https://cructi.ru/uplcv?utm_term=coroner+season+1+episode+1 PDF link annotation
    • http://santehnika34.ru/images/file/nevedakezilu.pdfIn PDF document text
    • http://medeeatour.ro/mm/file/dafevurozukidoraretazi.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/fepujomibesuvolamebirop.pdfIn PDF document text
    • https://e-ssuances.com/ckfinder/userfiles/files/90023701621.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/wugobefaziwepixas.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/98941072333.pdfIn PDF document text
    • https://renesens21.com/ressources/upload/files/muwulunupexamakozopofu.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/f8af95358d693b1cdf51f77cfa40acfb/9020600174.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/43433487988.pdfIn PDF document text
    • http://agmapure.com/upload/files/godiredazofopemilolizod.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/kitununepaxipegiresolala.pdfIn PDF document text
    • https://mygoaltv.com/ipp/images/uploads/files/jagamukuvifinimaze.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/vevidowadupuvonifux.pdfIn PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/gugalixewum.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149094156c95---39032555901.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161417689b1997---sadilibij.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/waxidarazitikubefeg.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1614d1ff0924ea---pufuvivodirizelinedof.pdfIn PDF document text
    • https://porfic.com/fotos/file/7078083710.pdfIn PDF document text
    • https://divetechmarine.com/contents/files/49178275656.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/52925859912.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/66384137275.pdfIn PDF document text
    • https://xn--b8qxb801j.tw/upload/files/jumutemopubozoxurumozepob.pdfIn PDF document text
    • https://kvizek.hu/ckfinder/userfiles/files/88293046424.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_off0000e1f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F2 10324 bytes
SHA-256: a0789c23d81c9162d133476f92e61f49ad2cd1b016288f02677f586eccd81966
font_01_sfnt_off0000f961.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF961 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011173.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11173 18676 bytes
SHA-256: f58e178f335dd9b8771b7461458b4b28f7313beefe4153161fca6fdfdf7ad0ce