CVE-2026-21909 (GCVE-0-2026-21909)
Vulnerability from cvelistv5
Published
2026-01-15 20:22
Modified
2026-01-15 20:52
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-401 - Missing Release of Memory after Effective Lifetime
Summary
A Missing Release of Memory after Effective Lifetime vulnerability in the routing protocol daemon (rpd) Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated attacker controlling an adjacent IS-IS neighbor to send a specific update packet causing a memory leak. Continued receipt and processing of these packets will exhaust all available memory, crashing rpd and creating a Denial of Service (DoS) condition.
Memory usage can be monitored through the use of the 'show task memory detail' command. For example:
user@junos> show task memory detail | match ted-infra
TED-INFRA-COOKIE 25 1072 28 1184 229
user@junos>
show task memory detail | match ted-infra
TED-INFRA-COOKIE 31 1360 34 1472 307
This issue affects:
Junos OS:
* from 23.2 before 23.2R2,
* from 23.4 before 23.4R1-S2, 23.4R2,
* from 24.1 before 24.1R2;
Junos OS Evolved:
* from 23.2 before 23.2R2-EVO,
* from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO,
* from 24.1 before 24.1R2-EVO.
This issue does not affect Junos OS versions before 23.2R1 or Junos OS Evolved versions before 23.2R1-EVO.
References
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Impacted products
| Vendor | Product | Version | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Juniper Networks | Junos OS |
Version: 23.2 ≤ Version: 23.4 ≤ Version: 24.1 ≤ |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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