FKIE_CVE-2026-21916
Vulnerability from fkie_nvd - Published: 2026-04-09 22:16 - Updated: 2026-04-17 18:05
Severity
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.
References
| URL | Tags | ||
|---|---|---|---|
| sirt@juniper.net | https://kb.juniper.net/JSA107807 | Mitigation, Vendor Advisory |
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| juniper | junos | * | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.2 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 23.4 | |
| juniper | junos | 24.2 | |
| juniper | junos | 24.2 | |
| juniper | junos | 24.2 | |
| juniper | junos | 24.2 | |
| juniper | junos | 24.2 | |
| juniper | junos | 24.2 | |
| juniper | junos | 24.2 | |
| juniper | junos | 24.4 | |
| juniper | junos | 24.4 | |
| juniper | junos | 24.4 | |
| juniper | junos | 24.4 | |
| juniper | junos | 24.4 | |
| juniper | junos | 24.4 | |
| juniper | junos | 25.2 | |
| juniper | junos | 25.2 | |
| juniper | junos | 25.2 | |
| juniper | junos | 25.2 |
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"value": "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."
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"id": "CVE-2026-21916",
"lastModified": "2026-04-17T18:05:52.693",
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"published": "2026-04-09T22:16:24.953",
"references": [
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
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.
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