Vulnerability-Lookup

GHSA-X5G9-73R3-VH5H

Vulnerability from github – Published: 2026-04-10 00:30 – Updated: 2026-04-10 00:30

Details

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

7.0 (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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-21916"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-61"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-09T22:16:24Z",
    "severity": "HIGH"
  },
  "details": "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.\n\nWhen after a user has performed a specific \u0027file link ...\u0027 CLI operation, another user commits (unrelated configuration changes), the first user can login as root.\n\nThis issue affects Junos OS:\n  *  all versions before 23.2R2-S7,\n  *  23.4 versions before 23.4R2-S6,\n  *  24.2 versions before 24.2R2-S3,\n  *  24.4 versions before 24.4R2-S2,\n  *  25.2 versions before 25.2R2.\n\n\nThis issue does not affect versions 25.4R1 or later.",
  "id": "GHSA-x5g9-73r3-vh5h",
  "modified": "2026-04-10T00:30:29Z",
  "published": "2026-04-10T00:30:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-21916"
    },
    {
      "type": "WEB",
      "url": "https://kb.juniper.net/JSA107807"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:U/V:X/RE:M/U:X",
      "type": "CVSS_V4"
    }
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-04-09 21:28 – Updated: 2026-04-10 03:56

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

CWE

CWE-61 - UNIX Symbolic Link (Symlink) Following

Assigner

juniper

References

URL

Tags

https://kb.juniper.net/JSA107807

vendor-advisory

Impacted products

	Vendor	Product	Version
	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

Date Public ?

2026-04-08 16:00

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-X5G9-73R3-VH5H

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

Tags

Sightings

Nomenclature