Malicious PDF — malware analysis report

Static analysis result for SHA-256 c927fb28bf71e8f3…

MALICIOUS

PDF

77.5 KB Created: 2021-09-28 03:08:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 04a6c9b36cd62e54b9a4ae75d01e4236 SHA-1: 441f6d02de428142e5d2f9fbcc41e73356b52133 SHA-256: c927fb28bf71e8f381b6927b9d7a85d33e42ae9114fc59173e7cb233949c972c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the exploitation of PDF vulnerabilities to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://queure.ru/uplcv?utm_term=how+to+save+a+web+article+as+a+pdf PDF link annotation
    • https://needlugs.com/userfiles/files/56989050261.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161418ae873589---dijedaji.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/makepusulile.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210926_A347890E41A4A532.pdfIn PDF document text
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109260830076820.pdfIn PDF document text
    • http://gintaras.cz/userfiles/file/lifizanutopojiguzapalex.pdfIn PDF document text
    • https://www.educazionesessuale-scuola.ch/ck/ckfinder/userfiles/files/kajeda.pdfIn PDF document text
    • https://jaurrieta.net/USERFILES_JAURRIETA/files/bitibixo.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/25009634231.pdfIn PDF document text
    • http://scarpatti.com/files/poruzunemotuwot.pdfIn PDF document text
    • http://portalpr-b2b.es/img/user//file/_0757075001632704746.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614278de997a9---45712628831.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/90f5f9e39bb19d8a425d67a7c91b8e3f/9388943486.pdfIn PDF document text
    • http://aviteksural.ru/admin/ckfinder/userfiles/files/fipadegugatimip.pdfIn PDF document text
    • http://asacnfservices.com/ckfinder/userfiles/files/98442362243.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613be0aa3135a---37485175095.pdfIn PDF document text
    • http://rsentco.com/upload/file/42672482293.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/sabex.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2f85c42cf---komagozupipopizalodubagi.pdfIn PDF document text
    • http://ahzgbh.news-read.com/upload/files/71746945711.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16146657e3b5ce---9418150961.pdfIn PDF document text
    • https://satellietgroep.nl/userfiles/files/94064407549.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_off0000c22e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC22E 10792 bytes
SHA-256: e63e882c58b831572979e866dba0d8da61f072a99d5ea7adc0ad6e3aa20d5507
font_01_sfnt_off0000dafd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f30f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF30F 20816 bytes
SHA-256: 043a05f532fb7e43d71a90aa0b02f9ee069f163dc787bad6bec0b0b5744863d3