Malicious PDF — malware analysis report

Static analysis result for SHA-256 f36fe74504f0b2d3…

MALICIOUS

PDF

84.0 KB Created: 2021-09-16 17:02:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3533270747f651e700589c83a2a4ca25 SHA-1: e365b94b62102f343630f334752cfefe7a1894c5 SHA-256: f36fe74504f0b2d3a6affb86f7b994006ce808992e7afe55eeb3efd5f50b98e8
174 Risk Score

Malware Insights

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

The sample is a PDF containing embedded JavaScript and external URIs, flagged by ML classifiers and ClamAV as malicious. The 'SE_CLICKFIX' heuristic indicates social engineering, instructing the user to run commands, likely to download and execute a secondary payload. The embedded JavaScript and external links suggest a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://zonazero.es/userfiles/file/vakixuwawimorepirawaza.pdf In PDF document text
    • http://lycee-elm.info/userfiles/file/gefiretugunoko.pdfIn PDF document text
    • http://teraval.cz/res/file/bubipegudexijopaduwimefak.pdfIn PDF document text
    • http://xn--2e0b95unoa536adofm5h.com/userfiles/file/notugujexazuvigir.pdfIn PDF document text
    • https://www.jdconstinc.com/ckfinder/userfiles/files/bekiguzuw.pdfIn PDF document text
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/7083993852.pdfIn PDF document text
    • http://technoauto.jp/js/upload/files/kasebakojekekotiro.pdfIn PDF document text
    • http://caycanhtuyhien.com/uploads/image/files/jewizavap.pdfIn PDF document text
    • https://kompaspt2.com/contents/files/22112071631.pdfIn PDF document text
    • http://apismorava.eu/docs/loxorekutixed.pdfIn PDF document text
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/96188750965.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/48078012985.pdfIn PDF document text
    • http://cleanyachts.it/writable/public/userfiles/file/61227541329.pdfIn PDF document text
    • http://czytamzezrozumieniem.pl/userfiles/file/45005392289.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358ce04de6b---jezedelutewikufotogoj.pdfIn PDF document text
    • https://cometgroupinternational.com/ckeditor/ckfinder/userfiles/files/7946280190.pdfIn PDF document text
    • https://keyword-lda.pt/site/upload/file/vuledifisufawovulu.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/uh0kamg5tqm9cr26kls5vm0213/wubizofenonidenovejo.pdfIn PDF document text
    • http://bebaldebaran.eu/userfiles/files/57669793027.pdfIn PDF document text
    • https://pgp-puh.hr/fck_media/file/62401326708.pdfIn PDF document text
    • http://cec-intl.ru/app/webroot/files/file/2174513713.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/tesovi.pdfIn PDF document text
    • https://semineebrasov.ro/printuri-fi/files/timisafevajumilujo.pdfIn PDF document text
    • https://avphunter.ro/ckfinder/userfiles/files/vabovovebujixu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=desactivar+servicios+de+google+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_off0000e1f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F0 18968 bytes
SHA-256: 40c4b35099b92aeb12ceca9bf65ef86e9f9ec684bfe925a92cf4cf286fa16e5e
font_01_sfnt_off0001125c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1125C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A73 10612 bytes
SHA-256: 26525b390704a395fc6b3f3ea3f98bfa7a88d1260c8a7ed5d9e9605f78ff9884