Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5131a50fd1d79a7…

MALICIOUS

PDF

80.2 KB Created: 2021-09-21 06:48:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 54cb5c278765beecb001fc0ddacd5ff8 SHA-1: 2a6c284dbf9ccb45dfa34f93ea2b74bb42c6489c SHA-256: f5131a50fd1d79a7dab0b8381b085e1905a191388c15af51cb53df5f5d9f2e4b
166 Risk Score

Malware Insights

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

This PDF document was flagged by ML classifiers and ClamAV as malicious, exhibiting characteristics of a phishing or social engineering attack. The 'SE_CLICKFIX' heuristic indicates the document attempts to trick users into running commands, likely to download and execute a secondary payload. While no scripts were directly extracted, the embedded URLs and the nature of the social engineering suggest an attempt to compromise the user's system.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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://interstudy.net/userfiles/file/11003747566.pdf In PDF document text
    • https://venusnvs.com/userfiles/file/56589340795.pdfIn PDF document text
    • http://imdmotors.com/uploadfile/file/2021092004140361.pdfIn PDF document text
    • http://ternovykh.ru/content/file/kesoxigo.pdfIn PDF document text
    • http://facyt.com.ar/ckfinder/userfiles/files/dibozijujemivazevuwop.pdfIn PDF document text
    • http://www.s-prom.si/fileupload/file/gadimi.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/33015559795.pdfIn PDF document text
    • https://prestinieurope.com/userfiles/files/wimoragesapavoruloruwubab.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/los4f8vfjiphjdsognf3pr1m29/99953669859.pdfIn PDF document text
    • http://www.hebrewforreadingcomprehension.com/content/68089024545.pdfIn PDF document text
    • https://fullprotec.com/ckfinder/userfiles/files/57799801225.pdfIn PDF document text
    • http://condosworld.com/abisol1/userfiles/files/7766388563.pdfIn PDF document text
    • https://alarrabnews.com/images/content/content/file/dipesaloxux.pdfIn PDF document text
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/4028473096.pdfIn PDF document text
    • https://semot.com/Store/userfiles/file/83828381622.pdfIn PDF document text
    • http://seatraderhk.com/userfiles/weroloj.pdfIn PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/64312876159.pdfIn PDF document text
    • http://sushibelovo.ru/files/tegojedinos.pdfIn PDF document text
    • http://ultraljud.nu/bild/files/wusezepezaled.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/xoton.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/02d146c788ee2ff1bad39dc5f6d4bc0f/nanuwurevexudulaf.pdfIn PDF document text
    • https://imagebrandstudio.com/userfiles/file/ribajubirorubixu.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/wobusakiwizodor.pdfIn PDF document text
    • https://maisonforville.be/documents/file/48756448656.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=find+saved+wifi+passwords+on+androidPDF 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_off0000d3f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3F7 17984 bytes
SHA-256: 6e767ccea62b6d0327dafb05a47dd4b85efb6d82549e5e64b93e272d4b427b30
font_01_sfnt_off000102bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ad4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AD4 10476 bytes
SHA-256: 0de7a2b1662a3ce7b3241e1ad00efe979e9f95fca78f965b3f68827ac3276ba8