CVE-2026-21921
Essential information
- Published
- 15/01/2026 21:16
- Modified
- 16/01/2026 15:55
- Author
- —
- Creator
- —
- CVSS
- 7.1 HIGH (v3) 7.1 HIGH (v4.0)
- CISA KEV
- No
- CWE
- —
- CVSS vector
-
—
—
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/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:A/V:X/RE:M/U:X
CVSS metrics
- Access vector
- —
- Access complexity
- —
- Authentication
- —
- Confidentiality impact
- —
- Integrity impact
- —
- Availability impact
- —
- Exploitability
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- —
- Attack complexity
- —
- Privileges required
- —
- User interaction
- —
- Scope
- —
- Confidentiality impact
- —
- Integrity impact
- —
- Availability impact
- —
- Exploit code maturity
- —
- Remediation level
- —
- Report confidence
- —
- Temporal score
- —
- Attack vector
- NETWORK
- Attack complexity
- LOW
- Attack requirements
- NONE
- Privileges required
- LOW
- User interaction
- NONE
- Confidentiality (V)
- NONE
- Confidentiality (S)
- NONE
- Integrity (V)
- NONE
- Integrity (S)
- NONE
- Availability (V)
- HIGH
- Availability (S)
- LOW
- Exploit maturity
- NOT_DEFINED
Description
A Use After Free vulnerability in the chassis daemon (chassisd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-based attacker authenticated with low privileges to cause a Denial-of-Service (DoS).
When telemetry collectors are frequently subscribing and unsubscribing to sensors continuously over a long period of time, telemetry-capable processes like chassisd, rpd or mib2d will crash and restart, which - depending on the process - can cause a complete outage until the system has recovered.
This issue affects:
Junos OS:
* all versions before 22.4R3-S8,
* 23.2 versions before 23.2R2-S5,
* 23.4 versions before 23.4R2;
Junos OS Evolved:
* all versions before 22.4R3-S8-EVO,
* 23.2 versions before 23.2R2-S5-EVO,
* 23.4 versions before 23.4R2-EVO.
NVD status
- Status
- Awaiting Analysis — CVE has been recently published to the CVE List and has been received by the NVD.
- Source
- [email protected]
- NVD
- View on NVD
Affected products (CPE)
| Product | CPE |
|---|---|
| juniper / junos os | cpe:2.3:o:juniper:junos_os:<22.4R3-S8:*:*:*:*:*:*:* |
| juniper / junos os | cpe:2.3:o:juniper:junos_os:<23.2R2-S5:*:*:*:*:*:*:* |
| juniper / junos os | cpe:2.3:o:juniper:junos_os:<23.4R2:*:*:*:*:*:*:* |
| juniper / junos os evolved | cpe:2.3:o:juniper:junos_os_evolved:<22.4R3-S8-EVO:*:*:*:*:*:*:* |
| juniper / junos os evolved | cpe:2.3:o:juniper:junos_os_evolved:<23.2R2-S5-EVO:*:*:*:*:*:*:* |
| juniper / junos os evolved | cpe:2.3:o:juniper:junos_os_evolved:<23.4R2-EVO:*:*:*:*:*:*:* |