Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7b4a97d73ba5f65…

MALICIOUS

PDF

84.2 KB Created: 2021-09-17 10:49:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 85c6ae74446d239ca1e8762683888ee1 SHA-1: 1f1c2e7fe0692bca0c9bfec94b058592f7aa92fe SHA-256: a7b4a97d73ba5f65aa0e923f331bdbe7360f1051901185601167c59ca712e039
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple external URIs and link farm heuristics supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://chcial.ru/uplcv?utm_term=elite+dangerous+fas PDF link annotation
    • http://sity-luxe.ru/userfiles/file/fumatolagowovaku.pdfIn PDF document text
    • http://www.bandungmesin.com/file/39971029960.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/dumeliromoxinexazop.pdfIn PDF document text
    • http://website-design-company.in/dev3/damodar/ckfinder/core/connector/php/userfiles/files/13425559166.pdfIn PDF document text
    • http://scuolascifondocortinadolomiti.it/userfiles/files/9015023105.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16137ee3bd299d---lojir.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/54722679531.pdfIn PDF document text
    • http://didula.ru/img/file/xofokigadiwixapijoti.pdfIn PDF document text
    • https://anakaygame.net/calisma2/files/uploads/45646155956.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16142fc6cbeab8---20372488178.pdfIn PDF document text
    • https://aneri12.eu/res/file/70587999429.pdfIn PDF document text
    • http://chrisdepanneservices.com/Sites/cds/files/59106704772.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210911_025932.pdfIn PDF document text
    • http://www.icf-plant.com/files/file/43993111341.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/42180631709.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613602ab2edc9---17342593357.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae8890abc4---nuper.pdfIn PDF document text
    • http://pizzeriadevita.it/userfiles/files/tegudezo.pdfIn PDF document text
    • https://horgaszvelem.hu/ckfinder/userfiles/files/dafatuxizadudajobemi.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/38540058323.pdfIn PDF document text
    • http://jurabos.nl/include/editor/file/vugekajexugovuvu.pdfIn PDF document text
    • https://papiratisk.cz/soubory/dojavifafu.pdfIn PDF document text
    • http://dtmaso.com/public_html/Imagens/file/42592348448.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16143f12eec893---gigeduzasipe.pdfIn PDF document text
    • http://robbes.nl/media/files/junobamagazaka.pdfIn PDF document text
    • http://cermak-expo.cz/data/files/file/88631138661.pdfIn PDF document text
    • http://didula.com/img/file/rejujuzitizetamobuz.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_off0000e715.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE715 17068 bytes
SHA-256: a8a10303804ea84d2efe39d8921a0ae5fde71c6daa990999c2d33d59751a0cbe
font_01_sfnt_off000112c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012adc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ADC 10612 bytes
SHA-256: fc558d2f5f95cd9127ac8f884ac2d8e4f0acb4acec91699dbc445c1f53884d08