CVE-2021-0215

CVE-2021-0215 is a medium-severity vulnerability in Juniper Junos with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-401.

Key facts

Description

On Juniper Networks Junos EX series, QFX Series, MX Series and SRX branch series devices, a memory leak occurs every time the 802.1X authenticator port interface flaps which can lead to other processes, such as the pfex process, responsible for packet forwarding, to crash and restart. An administrator can use the following CLI command to monitor the status of memory consumption: user@device> show task memory detail Please refer to https://kb.juniper.net/KB31522 for details. This issue affects Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D54; 15.1X49 versions prior to 15.1X49-D240 ; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S8; 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10 ; 18.2 versions prior to 18.2R2-S7, 18.2R3-S3; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R1-S7, 18.4R2-S4, 18.4R3-S2; 19.1 versions prior to 19.1R1-S5, 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S3, 19.3R3; 19.4 versions prior to 19.4R1-S2, 19.4R2. This issue does not affect Juniper Networks Junos OS 12.3, 15.1.

Frequently asked questions

What is CVE-2021-0215?
On Juniper Networks Junos EX series, QFX Series, MX Series and SRX branch series devices, a memory leak occurs every time the 802.1X authenticator port interface flaps which can lead to other processes, such as the pfex process, responsible for packet forwarding, to crash and restart. An administrator can use the following CLI command to monitor the status of memory consumption: user@device> show task memory detail Please refer to https://kb.juniper.net/KB31522 for details. This issue affects Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D54; 15.1X49 versions prior to 15.1X49-D240 ; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S8; 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10 ; 18.2 versions prior to 18.2R2-S7, 18.2R3-S3; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R1-S7, 18.4R2-S4, 18.4R3-S2; 19.1 versions prior to 19.1R1-S5, 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S3, 19.3R3; 19.4 versions prior to 19.4R1-S2, 19.4R2. This issue does not affect Juniper Networks Junos OS 12.3, 15.1.
How severe is CVE-2021-0215?
CVE-2021-0215 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-0215 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-0215?
CVE-2021-0215 primarily affects Juniper Junos. In total, 221 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-0215?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-0215 published?
CVE-2021-0215 was published on 2021-01-15 and last updated on 2026-06-17.

References

Affected products (221)

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