CVE-2021-0289 — Time-of-check Time-of-use (TOCTOU) Race Condition in Networks Junos OS
Severity
5.3MEDIUMNVD
CNA6.5
EPSS
0.1%
top 80.61%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedJul 15
Latest updateMay 24
Description
When user-defined ARP Policer is configured and applied on one or more Aggregated Ethernet (AE) interface units, a Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability between the Device Control Daemon (DCD) and firewall process (dfwd) daemons of Juniper Networks Junos OS allows an attacker to bypass the user-defined ARP Policer. In this particular case the User ARP policer is replaced with default ARP policer. To review the desired ARP Policers and actual state one can run the comman…
CVSS vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 1.6 | Impact: 3.6
Affected Packages2 packages
🔴Vulnerability Details
2GHSA▶
GHSA-2xhh-mjxg-mxhc: When user-defined ARP Policer is configured and applied on one or more Aggregated Ethernet (AE) interface units, a Time-of-check Time-of-use (TOCTOU)↗2022-05-24
CVEList▶
Junos OS: User-defined ARP Policer isn't applied on Aggregated Ethernet (AE) interface until firewall process is restarted↗2021-07-15
📋Vendor Advisories
1Juniper▶
CVE-2021-0289: When user-defined ARP Policer is configured and applied on one or more Aggregated Ethernet (AE) interface units, a Time-of-check Time-of-use (TOCTOU)↗2021-07-15