Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6e5505a3cd067b5…

MALICIOUS

PDF

67.8 KB Created: 2021-06-09 06:47:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 891f872cd2600175699157bc072f0cdd SHA-1: 074a805fd06202b40bb6899f7a2f872b10794fee SHA-256: b6e5505a3cd067b5f3c0e5f563cc89c25f323d1ceff960454173a552016d0f80
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the presence of numerous embedded URLs and the heuristic firings point towards a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://pistant.ru/uplcv?utm_term=concentration+calculations+worksheet+answers PDF link annotation
    • http://alexanderkanevskyartistbiography.com/clientMedia/file/selifirafosufawerowevo.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160812efd92b0d---nojurexugebeleruxafaxono.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/a4a4b2ecca90ff23237179e0872082b5/45597366505.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0b97bcb1d---90947350765.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609c2c742b2f5---72954676419.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160753ff5528fb---74126877868.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/bapofaj.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1609830d2770a8---rowisu.pdfIn PDF document text
    • http://bakoca.hu/files/file/34812871924.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a67973cdec5---bidazobovifomubelaz.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160afdbc63cc58---66484351632.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16099863e05795---foziwexota.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16093002a0764c---sinelobabowo.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/zolekotirulusibuzomuf.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/59421068705.pdfIn PDF document text
    • http://fontawesome.iohttp://fontawesome.io/license/In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC507 1636 bytes
SHA-256: caef7cd39e5a663dedc27031c9070b3104669c130e567e73d724f0d34b000ef7
font_01_sfnt_off0000cd35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD35 4948 bytes
SHA-256: 8f34ab8af5eb8b712c0f335dc559a407605bfa56e52c93bfa7866965135931df
font_02_sfnt_off0000de11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE11 10248 bytes
SHA-256: d68e89868d2c78750d7478dfcf482ff1e2afa9700e53bc6e90d7cd1111c2c864