Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef778c0bd3b9992f…

MALICIOUS

PDF

80.8 KB Created: 2021-09-03 10:09:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8181c804f07edd8509852f184678046b SHA-1: 047a1b5cf4bc411696f818605530d33d404934d0 SHA-256: ef778c0bd3b9992f2f733d9bbefecefb174a36c4a5a550c77894f017006570f6
156 Risk Score

Malware Insights

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

This PDF was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous links pointing to compromised WordPress sites and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of multiple external URIs and link farms indicates an attempt to direct users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c444c8c3101---79591573900.pdf In PDF document text
    • http://huefpdf.org/upload/file/pikuvutezurazoxepok.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/posegitalodi.pdfIn PDF document text
    • https://pui-vital.ro/msg_media/file/14891987640.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/codjg0tinabbbf40ba5f5um3v6/nopazixemo.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/963vqaegvn45u7cd3r1tdfk01j/51229047819.pdfIn PDF document text
    • http://imhkayseri.com/resimler/files/lejanid.pdfIn PDF document text
    • http://alpinist.store/sribati/editor/uploadfiles/258167318.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/xatuxuzarinu.pdfIn PDF document text
    • http://kcde.kr/userfiles/file/6248713680.pdfIn PDF document text
    • http://infinity-pro.ru/userfiles/file/38836750088.pdfIn PDF document text
    • http://johncarroll1967.com/clients/1/18/1896e795ecc2602204d707ec4e69586f/File/67273006610.pdfIn PDF document text
    • https://zohopin.com/calisma2/files/uploads/fagux.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/6970f301388d646c207cd404debdc2a7/14624684266.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/0ade66b63e5a2ca3772f6227710c12e2/86036755370.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/191e1125c2663cb4464d6cf0cecba13b/63887954240.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b26ae16fac2---14351997728.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/45481362935.pdfIn PDF document text
    • https://tidurmalam.com/contents//files/85056851587.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607aca6ec6e22---zebovogakutevitu.pdfIn PDF document text
    • https://alquimia.in/admin/fckeditor/editorfile/mekuzutelediwujikoze.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/316234998.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/lesesulaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=conceptual+design+architecture+pdfPDF 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_off0000d7d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D6 17048 bytes
SHA-256: e8e85752581f7b529a02c25e154525ae4eb37ca7ea32680932137660d61724a6
font_01_sfnt_off000103e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E8 11028 bytes
SHA-256: 8f2f5fed9e29c59701ff92a8572300b249c4817f97e458abd7cd826319d61be1
font_02_sfnt_off00011d48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D48 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1