Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c9fb21ca41e6520…

MALICIOUS

PDF

71.6 KB Created: 2021-09-09 17:59:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 272465f6b46c17af5e9bfcb8e38c3872 SHA-1: 1e9242d89887da7e4b382d789792ca0491b3fc5e SHA-256: 4c9fb21ca41e65203c74da09e32b5fbc9b5b5b2580d04eb59ee8467c2b844e10
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs and heuristics indicate it functions as a link farm, directing users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest 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 0.9956

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://garglob.ru/uplcv?utm_term=lo+que+no+te+mata+te+hace+mas+fuerte+pdf PDF link annotation
    • https://officialbacknumber.org/editor_up/nugomojomi.pdfIn PDF document text
    • https://dpengineers.info/admin/userfiles/file/bitomepojog.pdfIn PDF document text
    • http://www.slappedtogether.com/editoruploadfiles/file/33724218057.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/39536466468.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/47373317076.pdfIn PDF document text
    • http://tvoirostov.ru/ckfinder/userfiles/files/jiwujamiminapenedazox.pdfIn PDF document text
    • http://hometextiles-consultant.com/ckfinder/userfiles/files/38106900402.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d4db730b7---pizapofazudoriveb.pdfIn PDF document text
    • https://nichecnk.leaddeehub.com/userfiles/files/75182114932.pdfIn PDF document text
    • http://cistenivytahu.cz/upload/file/60225831332.pdfIn PDF document text
    • http://www.huntsvillepr.com/files/files/13877404168.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/72305856631.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/mupiwitudalobonikivomo.pdfIn PDF document text
    • http://www.themixchange.com/userfiles/files/93951257.pdfIn PDF document text
    • http://brenderup.ro/mm/file/dowixozib.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/kujolulakekageterazap.pdfIn PDF document text
    • https://pmrmhss.com/userfiles/file/91957166061.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f00b4abcaf---22581253655.pdfIn PDF document text
    • https://jagominum.com/contents/files/23394619226.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/9bc061eb93b8517442914ef2ebf47081/33006886086.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/kexeserupa.pdfIn PDF document text
    • https://mastirz.com/userfiles/files/80808730676.pdfIn PDF document text
    • https://hamayeshniroo.com/shop/file/katofepeg.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_off0000b41e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB41E 10952 bytes
SHA-256: 67f172256a6892f4e50efdec34ccfcaf68357ef712e1598d3528d75d7127b965
font_01_sfnt_off0000cd19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e52b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52B 17016 bytes
SHA-256: 91659a4523d09eea0d018941cc4aee3e9c08cc6610d5e969e2de97ac45c3c15e