Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb59d2fe35e9a287…

MALICIOUS

PDF

120.1 KB Created: 2021-06-09 23:43:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: e29d5da9ce7637d43f8bc3dee144dd1e SHA-1: 546d6619575fbeaa1ba5e9d8ee7195d780a18a7b SHA-256: cb59d2fe35e9a287a7ad11734c5fbd626744fafd0168460c75512309068d9a58
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://chcial.ru/uplcv?utm_term=number+worksheet+for+ukg PDF link annotation
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16078b15681068---81881882930.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/3180b41c80b5dbf97ca2200ee6d71460/20591328461.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba3888cf0e6---vasogapumimilosisulepemog.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160968759805c2---goragoreler.pdfIn PDF document text
    • http://falerisztika.hu/tmp/39955042420.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/25cebe24872c8ecb3bf40be610542820/wudovakudufanobaviki.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160701677ca357---jonozepis.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/guzudigefapidewagowekev.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16074cfd3b0038---libiwelanugefabanow.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7c244c45d---91694073150.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607d937708892---sikoruzetabu.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/io1stfvhandev7o27d93jdlku1/33247484867.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/58854500417.pdfIn PDF document text
    • https://babamore.com/upload/ckfinder_temp/files/20210601180336.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
    • http://fedorahosted.org/lohitIn 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001694d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1694D 4932 bytes
SHA-256: c612680d6a39321c2372ed092f3ad61159b94d5e26f7d749b0fac6169b361bc7
font_01_sfnt_off00017a37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17A37 11152 bytes
SHA-256: c5d71e2311f55f69368d00ee936c714bae7b45a598d4770f1931a7525a2aeae7
font_02_sfnt_off00019fb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19FB6 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
font_03_sfnt_off0001adb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1ADB6 12260 bytes
SHA-256: 1ae3c3863bed509919c2210618cbbd6cb952cf78aea2464de96fd930d4a5059c