CVE-2021-0244
published 2021-04-22CVE-2021-0244: A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific protection…
PriorityP338high7.4CVSS 3.1
AVNACLPRNUIRSCCNINAH
EPSS
0.64%
46.5th percentile
A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific protection mechanism to avoid a race condition which may allow an attacker to bypass the storm-control feature on devices. This issue is a corner case and only occurs during specific actions taken by an administrator of a device under certain specifics actions which triggers the event. The event occurs less frequently on devices which are not configured with Virtual Chassis configurations, and more frequently on devices configured in Virtual Chassis configurations. This issue is not specific to any particular Junos OS platform. An Indicator of Compromise (IoC) may be seen by reviewing log files for the following error message seen by executing the following show statement: show log messages | grep storm Result to look for: /kernel: GENCFG: op 58 (Storm Control Blob) failed; err 1 (Unknown) This issue affects: Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D49 on EX Series; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D191, 15.1X49-D200 on SRX Series; 16.1 versions prior to 16.1R7-S7; 16.2 versions prior to 16.2R2-S11, 16.2R3; 17.1 versions prior to 17.1R2-S11, 17.1R3; 17.2 versions prior to 17.2R2-S8, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S7; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S6, 18.2R3; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.
Affected
30 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| juniper | ex_series | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos_os | — | — |
| juniper | srx_series | — | — |
| juniper_networks | junos_os | >= 14.1X53 < 14.1X53-D49 | 14.1X53-D49 |
| juniper_networks | junos_os | >= 15.1 < 15.1R7-S6 | 15.1R7-S6 |
| juniper_networks | junos_os | >= 15.1X49 < 15.1X49-D191, 15.1X49-D200 | 15.1X49-D191, 15.1X49-D200 |
| juniper_networks | junos_os | >= 16.1 < 16.1R7-S7 | 16.1R7-S7 |
| juniper_networks | junos_os | >= 16.2 < 16.2R2-S11, 16.2R3 | 16.2R2-S11, 16.2R3 |
| juniper_networks | junos_os | >= 17.1 < 17.1R2-S11, 17.1R3 | 17.1R2-S11, 17.1R3 |
| juniper_networks | junos_os | >= 17.2 < 17.2R2-S8, 17.2R3-S3 | 17.2R2-S8, 17.2R3-S3 |
| juniper_networks | junos_os | >= 17.3 < 17.3R2-S5, 17.3R3-S7 | 17.3R2-S5, 17.3R3-S7 |
| juniper_networks | junos_os | >= 17.4 < 17.4R2-S9, 17.4R3 | 17.4R2-S9, 17.4R3 |
CVSS provenance
nvdv3.17.4HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:N/A:P
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Juniper
CVE-2021-0244: A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific pr
vendor_juniper·2021-04-22·CVSS 7.4
CVE-2021-0244 [HIGH] CWE-362 CVE-2021-0244: A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific pr
CVE-2021-0244: A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific protection mechanism to avoid a race condition which may allow an attacker to bypass the storm-control feature on devices. This issue is a corner case and only occurs during specific actions taken by an administrator of a device under certain specifics actions which triggers the event. The event occurs less frequently on devices which are not configured with Virtual Chassis configurations, and more frequently on devices configured in Virtual Chassis configurations. This issue is not specific to any particular Junos OS platform. An Indicator of Compromise (IoC) may be seen by reviewing log files for the following error message see
GHSA
GHSA-6w22-mmhg-hxh2: A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific pr
ghsa_unreviewed·2022-05-24
CVE-2021-0244 [HIGH] CWE-362 GHSA-6w22-mmhg-hxh2: A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific pr
A signal handler race condition exists in the Layer 2 Address Learning Daemon (L2ALD) of Juniper Networks Junos OS due to the absence of a specific protection mechanism to avoid a race condition which may allow an attacker to bypass the storm-control feature on devices. This issue is a corner case and only occurs during specific actions taken by an administrator of a device under certain specifics actions which triggers the event. The event occurs less frequently on devices which are not configured with Virtual Chassis configurations, and more frequently on devices configured in Virtual Chassis configurations. This issue is not specific to any particular Junos OS platform. An Indicator of Compromise (IoC) may be seen by reviewing log files for the following error message seen by executing
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2021-04-22
Published