Malicious PDF — malware analysis report

Static analysis result for SHA-256 c936c01b69e8e1c3…

MALICIOUS

PDF

75.6 KB Created: 2021-10-04 10:37:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 44eebf7a72502ee3716609006b6522cd SHA-1: 87446e87300facc1472037ed802aff0125df5301 SHA-256: c936c01b69e8e1c38b17540c42beb92ee2ae446567bbf611e57a815a78818a1f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm. Several extracted URLs point to compromised CMS uploads or disposable hosting, suggesting an attempt to distribute malicious content or phish users. The document body was unreadable, but the presence of numerous links to external sites strongly indicates a malicious intent to redirect the user.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://nexxosrealty.com/userfiles/files/lixusemo.pdf In PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613d35211dca4---lovobubejelesanixideziwuf.pdfIn PDF document text
    • http://studioschicchi.eu/userfiles/files/kupawaf.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/17ac1febf5d7455a36289647a946109b/17689610260.pdfIn PDF document text
    • http://borneneskontor-landsforening.dk/userfiles/file/jipolowilikadimibelavaler.pdfIn PDF document text
    • https://hoangphatdanang.com/uploads/image/files/xopokatida.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/sadozarokadelekujudo.pdfIn PDF document text
    • http://wjvanderheidedienstverlening.nl/uploads/file/82267718260.pdfIn PDF document text
    • http://cupta.org/userfiles/files/20211004075717.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/59ae2d43a2f5eae8de4b06968da8a1cb/lamugijegarizuf.pdfIn PDF document text
    • https://actor-conseil.com/files/file/kovesipakuji.pdfIn PDF document text
    • http://www.deep2001.com/images/library/File/10562729427.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/gitaxeramikalika.pdfIn PDF document text
    • http://tourhong.com/FileData/ckfinder/files/20211003_5AD4DEAFC4B60E4C.pdfIn PDF document text
    • http://lexen.ca/userfiles/files/21543824290.pdfIn PDF document text
    • http://es-iyashinomori.net/yamituki-n/uploads/files/54460051015.pdfIn PDF document text
    • http://nyett.hk/uploads/news/files/rinurigesop.pdfIn PDF document text
    • http://skia22.ru/pic/file/purisevasosepegesolila.pdfIn PDF document text
    • https://uzmanwebci.com/calisma2/files/uploads/76836607478.pdfIn PDF document text
    • https://dalba.net/other_files/File/sudedututagokopogin.pdfIn PDF document text
    • http://dogwarts.ru/sites/default/files/file/3839715223.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/kevesanok.pdfIn PDF document text
    • https://gsacademy.ge/uploads/files/rufifavesixo.pdfIn PDF document text
    • https://maxflowfans.com/userfiles/file/28785585836.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=genetics+the+science+of+heredity+answersPDF 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_off0000bcee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCEE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d500.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD500 19608 bytes
SHA-256: 845ad94aed8b8762473e213b9f660c63896cce1610330feb4074afca1018a87a
font_02_sfnt_off000107ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107FF 10764 bytes
SHA-256: 2eb5574911ad1a604b99216122cbb00d52d4965f256c1cba3a8e81a7a3e52d64