Malicious PDF — malware analysis report

Static analysis result for SHA-256 6738589c99cc1f62…

MALICIOUS

PDF

78.8 KB Created: 2021-09-10 22:56:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c115870e5989cd4f2b1a196c23cf9881 SHA-1: e15e1c1f59b078a4556593b9bcdd0b0aaaa493f4 SHA-256: 6738589c99cc1f628a8dee6b597f10387c724589b50346fd8df3d4f38fd58eb3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to various websites, many of which appear to be compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of external URIs and link farms suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://allytemp.ru/uplcv?utm_term=clownfish+voice+apk PDF link annotation
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/856ca561de7145e8ea2c21ad7d34d10c/75759286209.pdfIn PDF document text
    • http://stnicholasway.com/userfiles/file/sorijo.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/zaxiwudotan.pdfIn PDF document text
    • https://888nv.ru/userfiles/file/sutujibexaxonanobawo.pdfIn PDF document text
    • https://ms02bet.net/contents/files/32337976978.pdfIn PDF document text
    • http://slstudio.it/userfiles/files/21999227730.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16135d98215cff---41759556335.pdfIn PDF document text
    • https://birotex.rs/images/files/87481357990.pdfIn PDF document text
    • http://www.neoneophytou.com/ckfinder/userfiles/files/65125212107.pdfIn PDF document text
    • https://icrs-as.com/userfiles/file/47583803888.pdfIn PDF document text
    • http://www.giuseppe.ru/ckfinder/userfiles/files/50713460479.pdfIn PDF document text
    • http://cke.hk/userfiles/41625356645.pdfIn PDF document text
    • http://armanetti.com/images/43595932121.pdfIn PDF document text
    • http://nhungbaithuocnam.com/img-tvdl/files/41026720882.pdfIn PDF document text
    • https://congthuonghotel.vn/app/webroot/files/images/pages/files/18803601518.pdfIn PDF document text
    • https://epgeptech.hu/ckfinder/userfiles/files/562831943.pdfIn PDF document text
    • http://siamintertrade.com/file_media/file_image/file/zarabumo.pdfIn PDF document text
    • http://merlegdoktor.hu/tmp/mababuvesoripomewotan.pdfIn PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/nutoxodikedanesasura.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/819f591d1ade92fcd8abdc47e9ac057a/fizuzokusa.pdfIn PDF document text
    • http://24horasnoar.com.br/ckfinder/userfiles/files/gunodutuvufo.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_off0000cfca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFCA 17612 bytes
SHA-256: dc70a3b49529920eb4d21b28f241fc69783f553793f5f3a08fa88e52d22a98cf
font_01_sfnt_off0000fd3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3F 10652 bytes
SHA-256: 670b795f113175f3f451c97a77ade46babba4bc7086a0d382ad92840a721c2fa
font_02_sfnt_off000115ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1