Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb0854767752c053…

MALICIOUS

PDF

73.4 KB Created: 2021-09-09 15:06:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: b9ac274b43d7a906f7ed1363bb8b69dc SHA-1: cd27bb91baf64b880066deb22794ab4643bfdb5b SHA-256: cb0854767752c0538fcf460c69356f08edb6224c91724a0ea96346fbc628d96d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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 0.9951

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://laborke.ru/uplcv?utm_term=deadly+snakes+in+australia PDF link annotation
    • http://sochisushi.nl/survey/userfiles/files/50449768161.pdfIn PDF document text
    • http://szybkieprawko.pl/szybkieprawko.pl/user/admin/fck/file/90212217016.pdfIn PDF document text
    • http://kayapaliinsaat.net/file/zajifatipasejabejirasa.pdfIn PDF document text
    • https://theipbuzz.com/images/file/24035442231.pdfIn PDF document text
    • http://hzdsbg.cn/uploadfile/1630922790.pdfIn PDF document text
    • https://unitytradecapital.com/ckfinder/userfiles/files/badupifiv.pdfIn PDF document text
    • https://mintowncoffee.net/uploads/images/files/71257212816.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/2f186bf70a8475dd379bfed8c6c2d81d/pixesejolaxawupixevup.pdfIn PDF document text
    • http://toyotarent.tw/FileData/ckfinder/files/20210902_3D15915BDB5C757E.pdfIn PDF document text
    • http://bienchidan.org/uploads/files/60161335039.pdfIn PDF document text
    • http://loadcell.vn/Images_upload/files/zuwevuxegan.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/pixaralurisumijaferexux.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/90ed03defa4240c8b119e6399fffc060/53173075098.pdfIn PDF document text
    • http://chiengthai.com/file_media/file_image/file/dawanufevusutakebasudosu.pdfIn PDF document text
    • http://dataprint.ie/uploads/file/lumobufezuzejol.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/56360512265.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/v1nsi45cfatuv8j9qe3sbns4f7/sagajetinafufedupakevif.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/kigafavedavejalagajib.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/52096128258.pdfIn PDF document text
    • https://segurodegranizo.ar/noticias/fckeditor/file/zovadixipomavitalexixif.pdfIn PDF document text
    • http://aaykpn.com/uploads/editor/files/kuwew.pdfIn PDF document text
    • https://g55net.com/webpagebuilder/ckfinder/userfiles/files/gofim.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/pewivovuvozena.pdfIn PDF document text
    • http://factblogs.com/uploaded_files/userfiles/files/favipusunatelafakok.pdfIn 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://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_off0000bc9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC9E 17096 bytes
SHA-256: 76d1f155eaf06090b6c27d4c06b7a768b4bb3f9f08032b2e590fec6af3be8f0a
font_01_sfnt_off0000e827.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE827 10428 bytes
SHA-256: 50fbeaa6d003be988102b2d31a9ec762c4d9bd4da0bc2b6de11c6306129e3b8e
font_02_sfnt_off0000ffec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1