Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e0b3eb7477f39d8…

MALICIOUS

PDF

85.2 KB Created: 2021-10-07 01:07:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: e550d4c63071614f33fc8eeb9bc5a725 SHA-1: f07d0c94c046d1bfe7a06cae6402604043c45551 SHA-256: 9e0b3eb7477f39d88591eeb1cb1b2a65d92280139d85de2e67dda7708cac2e49
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains a link farm pointing to numerous PDF files hosted on various domains, many of which appear to be compromised or disposable. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a deliberate attempt to obscure the final destination and leverage potentially compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://biosafety.biz/ckfinder/userfiles/files/dejasivar.pdf In PDF document text
    • http://qdjshg.com/files/file/94995886171.pdfIn PDF document text
    • https://euchebnici.com/img/file/fiberegolurevoxo.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/15554861818.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16159b124d4767---13987345954.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c4e8c76e1---wufaxixit.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/titexaxabekepe.pdfIn PDF document text
    • https://attack.lt/images/files/dokugiletafimazesusapapa.pdfIn PDF document text
    • http://abwcolley.com/uploads/files/sarukeko.pdfIn PDF document text
    • http://xn--80ahcjevtqq.xn--p1ai/ckfinder/userfiles/files/sivegisafalot.pdfIn PDF document text
    • http://autodilykanka.cz/cmsimple/images/file/80101415795.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/b4453e03d093319251ecce7b2ed549b9/fozutuxexiwifaburojoni.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16154244748d08---dojogufajiduluvinuban.pdfIn PDF document text
    • http://abwlondonblvd.com/uploads/files/457410087.pdfIn PDF document text
    • https://maritime-models.com/userfiles/file/laromup.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16150c13d5d227---kupen.pdfIn PDF document text
    • http://briquettemachinery.com/d/files/15924828679.pdfIn PDF document text
    • http://szybkieprawko.pl/szybkieprawko.pl/user/admin/fck/file/43062248176.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/c1a8a886d4a1b34b89955412daac8082/19419301358.pdfIn PDF document text
    • https://implant-drill.com/userfiles/file/86087569468.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=why+do+dogs+eat+grass+when+nauseousPDF 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_off0000e58d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD9F 19140 bytes
SHA-256: 803cb3a8771e711c1ab9eee1a1351e8cad2518bb9ea10cead65b735a5437d126
font_02_sfnt_off00012ebf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EBF 10684 bytes
SHA-256: 337733cdf5ba54ede9f814773fd73749d6b27885f600f4ed420f70ab2eb6e354