Malicious PDF — malware analysis report

Static analysis result for SHA-256 b28812ae1f8e9bb1…

MALICIOUS

PDF

75.6 KB Created: 2021-09-28 03:54:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 036053a9d7a6c216bfd505f09aeed7a8 SHA-1: 69f4b7d10bee338882eea33fe391b2d8c754cea6 SHA-256: b28812ae1f8e9bb1c968df9ca5f345c5ee250fde5704d816079527d10d202e9d
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, pointing towards an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://tahyuh.com/uploads/files/202109082218163360.pdf In PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/20398139251.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613790bb59b81---gikajemuxosezewozefezefat.pdfIn PDF document text
    • http://gemcom.org/userfiles/file/mosigagiroladix.pdfIn PDF document text
    • https://renhedc.com/uploads/files/202109010914269307.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/kivugaf.pdfIn PDF document text
    • https://glaze-metalart.com/upload/files/golixenuxubipibuxubogizu.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca13adea99---88728864476.pdfIn PDF document text
    • http://tt-ural.su/admin/ckfinder/userfiles/files/wenomij.pdfIn PDF document text
    • http://qianxi.cn/filespath/files/20210901210902.pdfIn PDF document text
    • http://santeh.md/img/files/kodavemek.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/27496610735.pdfIn PDF document text
    • http://p-energo.ru/content/file/51806345893.pdfIn PDF document text
    • http://expresskaliski.info/file/50449355193.pdfIn PDF document text
    • http://umrllc.com/userfiles/files/nogipej.pdfIn PDF document text
    • http://cudicio.it/images/file/21742674593.pdfIn PDF document text
    • https://rewaqousha.net/userfiles/files/zijokaraxu.pdfIn PDF document text
    • http://twapp.freshkon.com/upload/files/72170058467.pdfIn PDF document text
    • http://087334211.kad.tw/kads/ckfinder/userfiles/files/lexegepol.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/50217668483.pdfIn PDF document text
    • https://gizaviation.com/uploads/files/69129448502.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/67614518295.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132a14318b09---36133890375.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=golf+hand+position+at+impactPDF 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_off0000b971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB971 10692 bytes
SHA-256: 263558ad129224ba6f79da00607f68579a23daa036450b2308452c4725972967
font_01_sfnt_off0000d1c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D8 20912 bytes
SHA-256: 0f73cbd0736abb534ce2f31a12a86136e32532316e52db7dac84bedf3883ad4c