Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f8b11cc81372ad7…

MALICIOUS

PDF

80.1 KB Created: 2021-09-03 07:46:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 83e856342895293efb7406fcff59d20b SHA-1: a950ba8b48231a6b9323de9e75a97aa75c9095dd SHA-256: 6f8b11cc81372ad7d38dfe6347d75a87e14c099b7ac3af67cd78cda887808e31
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of external URIs and link farms points towards an attempt to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608effaa8f5ba---26924560844.pdf In PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607307317804e---tojejozexoga.pdfIn PDF document text
    • https://shih-tzu.ro/files/file/55002483167.pdfIn PDF document text
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/a12f139407a2ebbd0facc1131d6f8742/16973289246.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e21296c442---jodonedadenij.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/71bdb888dc2fbe4571511d9425e86898/risizazajeriwedemedisi.pdfIn PDF document text
    • http://nhahanghienminh68.com/upload/files/rirol.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/o59uetuc3hneme662nju7vk4v5/2887959997.pdfIn PDF document text
    • http://villa-carlshorst.de/sites/default/files/file/90083133535.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/r2cbkcui45l92gc5ngcnho7156/16846014156.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/nejatujegidamalenamajukor.pdfIn PDF document text
    • http://richfield1960.com/clients/865265/File/16571007762.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c00767b8a43---rajiwufosabomax.pdfIn PDF document text
    • https://sardavetri.it/userfiles/file/litagofajumegetil.pdfIn PDF document text
    • http://mobitransjogja.com/files/sixufobirerekodizep.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b7e2e773bd0---17034298790.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/apexegiwawafot.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/9e4d94c1f8283fad69c29411166574d1/figegizegebumoponakib.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc0b26c8d8---vaduwarikepob.pdfIn PDF document text
    • https://gastrotest.co/ckfinder/userfiles/files/fuvepefoloxa.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb3a089e76---gisulolajefojadusera.pdfIn PDF document text
    • https://bloomeng.com/uploads/vuzel.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb591ef490---27545962713.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/susavesidererikibok.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/denoxujozid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=language+curriculum+design+nation+pdfPDF 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://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_off0000d4f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4F7 17072 bytes
SHA-256: 098a34f9e633dc173c65a0c3cb399c85732d2f56172877829c93815ab0fdc9cc
font_01_sfnt_off000100fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100FB 11020 bytes
SHA-256: adf6f4625100e98f8028cffe9f9855373ae90e65f2365086748317d203ce9d3c
font_02_sfnt_off00011a5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A5F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1