Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b8a149bca35fcaf…

MALICIOUS

PDF

103.4 KB Created: 2021-06-30 02:41:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f24c7460f9aec093d380a9c98cc942fb SHA-1: 5a995eb1f0f84582ac2ebb2dc22d65d01ce08a05 SHA-256: 3b8a149bca35fcaf56d6eadd16213f608f0706318090436404fd0b2995e8dfda
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF that exhibits characteristics of a phishing lure, specifically related to invoices or payments. It contains numerous external links, many of which point to compromised WordPress sites hosting further PDF documents, suggesting a distribution network. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a secondary payload or phish credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160db67e204290---97255330691.pdf
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/r87ke014mactetop8ibebb90o0/lesarifarax.pdf
    • https://maspacientes.es/wp-content/plugins/super-forms/uploads/php/files/6qio749bif8igt42tm83ljbc7t/46773746800.pdf
    • http://dragonera.cn/admin/userfiles/file/xudexovo.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/a18d22eb55f53d937e5cab82d05f6089/pavotorar.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/48umofo5m92lnnf2jeqmtoahvj/wobatasidinizaremopipom.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16080bbde466ec---buxiwebu.pdf
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/50ad563faad989f8cea6ef929f94a4d1/juwasusuz.pdf
    • https://ajwatravel.com/wheelmarine/userfiles/file/85169083853.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/3eqmbsk32of7civtg2s1lm16a0/36198739883.pdf
    • http://khaskhaan.mn/uploads/userfiles/files/dazugezusidipoveduja.pdf
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/fewixuvozepuratebekaduj.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7d53052c1---76988526473.pdf
    • http://adamlegal.com/userfiles/file/22470932738.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b10e5bae039---norugetimanigavowebeti.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/a149716527ff8a5a2981928ec9d3ee01/tamononezijoxana.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160868d6563495---barerixefaf.pdf
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f427d8d31e---37551995583.pdf
    • http://prinsart.ro/uploads/files/88533579183.pdf
    • http://hutbephottaihaiphong24h.com/upload/files/tonokijolasazamawovefogaf.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/e4b01hsgs3mtfgrimt8191ud02/sutanuxanenuvu.pdf
    • http://acril.ru/ufiles/files/1978878795.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fec7cd5c5b---58248214927.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=excel+calendar+template+2020+free
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012e44.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E44 16792 bytes
font_01_sfnt_off00014656.bin
b8b7543f5f36a072297c5a7caba9904f38ce4c0ac3d38cb3b567913057c8a38b
pdf-font-stream PDF embedded font (sfnt) at offset 0x14656 19032 bytes
font_02_sfnt_off000177fe.bin
2c39998e269e43781d434b62cc06e4a17b1cdec64780bd9b9c993d0441514017
pdf-font-stream PDF embedded font (sfnt) at offset 0x177FE 10728 bytes