Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5d57f6f14891c6f…

MALICIOUS

PDF

85.6 KB Created: 2021-06-20 06:15:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 8d83fd57d004369a5414181701483b19 SHA-1: 7ca55b3ced15c45003dad43117a2ee6fea4bdce2 SHA-256: a5d57f6f14891c6f1ea50dcf390005e056bb2de391bde27be30228a9770dac3b
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it's designed to lure users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The document body is unreadable, but the heuristics and URL analysis point to a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://too.kg/wp-content/plugins/super-forms/uploads/php/files/6bfb01fcd60eb90bab23df4a80d08fd1/22751660027.pdf In PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16083dcb30f919---24221170246.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c04d73f2590---33719007746.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/0939885eb54af293312d40216f746cfe/wamedusoliroliloduw.pdfIn PDF document text
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/jimevujuzonoguxamexoxa.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1609c35cd66538---kasezel.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8949a8305---34953745.pdfIn PDF document text
    • http://doverhighschoolhalloffame.com/clients/2/2d/2d76883e1086210ef8e2c43836b0327f/File/kufapewo.pdfIn PDF document text
    • http://diysmart.net/userfiles/file/81019612963.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/738b74053de9da26aec3cf285b100975/61561118035.pdfIn PDF document text
    • https://local-atlas.ru/userfiles/files/tazow.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/mosabulemosuzo.pdfIn PDF document text
    • http://chsbicentennialclassof1976.com/clients/c/c2/c283bfa2537a82fb79a670aa087b4bd4/File/vusaripopunazebepo.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/34629312799.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c61aaf859f5---julosus.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/73510712965.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=d%2526d+pirate+character+sheetPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010980.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10980 3484 bytes
SHA-256: 865832ca46ee1aac596e2af09c34c3d6059d9ba0f9f4eea226865a594599e1c6
font_01_sfnt_off000114ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114ED 11496 bytes
SHA-256: 354d3b8519908ab512829fe6645131461cc592240499762a609d4b20d5f53cff
font_02_sfnt_off00013c09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C09 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2