CVE-2026-21911 (GCVE-0-2026-21911)
Vulnerability from cvelistv5
Published
2026-01-15 20:23
Modified
2026-01-15 20:51
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-682 - Incorrect Calculation
Summary
An Incorrect Calculation vulnerability in the Layer 2 Control
Protocol
Daemon (l2cpd) of Juniper Networks Junos OS Evolved allows an unauthenticated network-adjacent attacker flapping the management interface to cause the learning of new MACs over label-switched interfaces (LSI) to stop while generating a flood of logs, resulting in high CPU usage.
When the issue is seen, the following log message will be generated:
op:1 flag:0x6 mac:xx:xx:xx:xx:xx:xx bd:2 ifl:13302 reason:0(REASON_NONE) i-op:6(INTRNL_OP_HW_FORCE_DELETE) status:10 lstatus:10 err:26(GETIFBD_VALIDATE_FAILED) err-reason 4(IFBD_VALIDATE_FAIL_EPOCH_MISMATCH) hw_wr:0x4 ctxsync:0 fwdsync:0 rtt-id:51 p_ifl:0 fwd_nh:0 svlbnh:0 event:- smask:0x100000000 dmask:0x0 mplsmask 0x1 act:0x5800 extf:0x0 pfe-id 0 hw-notif-ifl 13302 programmed-ifl 4294967295 pseudo-vtep underlay-ifl-idx 0 stack:GET_MAC, ALLOCATE_MAC, GET_IFL, GET_IFF, GET_IFBD, STOP,
This issue affects Junos OS Evolved:
* all versions before 21.4R3-S7-EVO,
* from 22.2 before 22.2R3-S4-EVO,
* from 22.3 before 22.3R3-S3-EVO,
* from 22.4 before 22.4R3-S2-EVO,
* from 23.2 before 23.2R2-S1-EVO,
* from 23.4 before 23.4R1-S2-EVO, 23.4R2-EVO.
References
| URL | Tags | |||||||
|---|---|---|---|---|---|---|---|---|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Juniper Networks | Junos OS Evolved |
Version: 0 ≤ Version: 22.2 ≤ Version: 22.3 ≤ Version: 22.4 ≤ Version: 23.2 ≤ Version: 23.4 ≤ |
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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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