CVE-2026-21916 (GCVE-0-2026-21916)

Vulnerability from cvelistv5 – Published: 2026-04-09 21:28 – Updated: 2026-04-13 13:04
VLAI
Title
Junos OS: A low privileged user can escalate their privileges so that they can login as root
Summary
A UNIX Symbolic Link (Symlink) Following vulnerability in the CLI of Juniper Networks Junos OS allows a local, authenticated attacker with low privileges to escalate their privileges to root which will lead to a complete compromise of the system. When after a user has performed a specific 'file link ...' CLI operation, another user commits (unrelated configuration changes), the first user can login as root. This issue affects Junos OS: * all versions before 23.2R2-S7, * 23.4 versions before 23.4R2-S6, * 24.2 versions before 24.2R2-S3, * 24.4 versions before 24.4R2-S2, * 25.2 versions before 25.2R2. This issue does not affect versions 25.4R1 or later.
Severity
7.3 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
7 (High)
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:L/AU:Y/R:U/RE:M
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-10 03:56 UTC
CWE
  • CWE-61 - UNIX Symbolic Link (Symlink) Following
Assigner
juniper CNA under the mitre root
CNA scorecard B 84/100 over 193 records in the last 180 days details
References
URL Tags
https://kb.juniper.net/JSA107807 vendor-advisory
Impacted products
Vendor Product Version CPE status
Juniper Networks Junos OS Affected: 0 , < 23.2R2-S7 (semver)
Affected: 23.4 , < 23.4R2-S6 (semver)
Affected: 24.2 , < 24.2R2-S3 (semver)
Affected: 24.4 , < 24.4R2-S2 (semver)
Affected: 25.2 , < 25.2R2 (semver)
Unaffected: 25.4R1
guessed Create a notification for this product.
Date Public
2026-04-08 16:00
Show details on NVD website
To clipboard 

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            "value": "Una vulnerabilidad de seguimiento de enlace simb\u00f3lico (Symlink) de UNIX en la CLI de Juniper Networks Junos OS permite a un atacante local, autenticado y con bajos privilegios escalar sus privilegios a root, lo que conducir\u00e1 a un compromiso completo del sistema.\n\nCuando, despu\u00e9s de que un usuario ha realizado una operaci\u00f3n CLI espec\u00edfica de \u2019file link ...\u2019, otro usuario confirma (cambios de configuraci\u00f3n no relacionados), el primer usuario puede iniciar sesi\u00f3n como root.\n\nEste problema afecta a Junos OS:\n  *  todas las versiones anteriores a 23.2R2-S7,\n  *  versiones 23.4 anteriores a 23.4R2-S6,\n  *  versiones 24.2 anteriores a 24.2R2-S3,\n  *  versiones 24.4 anteriores a 24.4R2-S2,\n  *  versiones 25.2 anteriores a 25.2R2.\n\nEste problema no afecta a las versiones 25.4R1 o posteriores."
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      "title": "Junos OS: A low privileged user can escalate their privileges so that they can login as root",
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}



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