Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cfb7cd16e6a802d…

MALICIOUS

PDF

74.9 KB Created: 2021-09-07 17:11:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1f7686fd67e17d7bcbbe8e5f69192c90 SHA-1: f2bfbbd3013bee068afef6a8fac5640e26577953 SHA-256: 8cfb7cd16e6a802db7eefba7fd658cb5860daf21d20f0cf10acf2428cf2ebb05
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to external PDF files hosted on domains flagged as link farms or potentially compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://adance0112.com/upfile/editor/file/64617347333.pdf In PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/25116148007.pdfIn PDF document text
    • http://ambvetfanini.eu/userfiles/files/wuteno.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20210519073008.pdfIn PDF document text
    • http://htwy.com/upload/file/93510849223.pdfIn PDF document text
    • http://yevres.fr/ckfinder/userfiles/files/motuje.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/51108760168.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094280d13330---xukoba.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/rawuwavo.pdfIn PDF document text
    • http://numere-mopede.ro/mm/file/51843818356.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/6bpo2392ndf4uc6mk5n1acf77o/bomorolepuraz.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/68080902006.pdfIn PDF document text
    • http://paroissedementon.fr/upload/files/losigosisijo.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2895d03b7e56a513de9eb93c750ad821/80222656896.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/77683231109.pdfIn PDF document text
    • https://praward.tw/wp-content/plugins/super-forms/uploads/php/files/5e427fd1f472296ed351b9c9bb436987/50778649044.pdfIn PDF document text
    • https://theipbuzz.com/images/file/2406272311.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/xozakimunisozinomofevo.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/mevakotobaxerepubix.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/0d81d5dee018dcb4685c5403aceed6c6/88897989847.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/50817025668.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16077da4369673---94122128006.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/15abimnapi9f8cpvua2gg5ehcp/molikebatilusemiwu.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a97e724433d---tidivunorulerinetusam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=adjectives+for+colors+and+shapes+worksheetsPDF 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_off0000bfdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFDF 16972 bytes
SHA-256: c96adcb69ff3770ff3ed2868cd9f1bb6ce8e8bc2ab9cce92149df2932bf0851d
font_01_sfnt_off0000ebb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB1 11072 bytes
SHA-256: 926c86534bcc67bae0cc02f96e7d4efe5e2cca6917338637af83cb8ef15068a7
font_02_sfnt_off00010577.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10577 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1