Vulnerability in Juniper Junos
CVE-2021-0264
A vulnerability in the processing of traffic matching a firewall filter containing a syslog action in Juniper Networks Junos OS on MX Series with MPC10/MPC11 cards installed, PTX10003 and PTX10008 Series devices, will cause the line card to crash and restart, creating a Denial of Service (DoS). Continued receipt and processing of packets matching the firewall filter can create a sustained Denial of Service (DoS) condition. When traffic hits the firewall filter, configured on lo0 or any physical interface on the line card, containing a term with a syslog action (e.g. 'term <name> then syslog'), the affected line card will crash and restart, impacting traffic processing through the ports of the line card. This issue only affects MX Series routers with MPC10 or MPC11 line cards, and PTX10003 or PTX10008 Series packet transport routers. No other platforms or models of line cards are affected by this issue. Note: This issue has also been identified and described in technical service bulletin TSB17931 (login required). This issue affects: Juniper Networks Junos OS on MX Series: 19.3 versions prior to 19.3R3-S2; 19.4 versions prior to 19.4R3-S2; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R2-S2, 20.2R3; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2. Juniper Networks Junos OS Evolved on PTX10003, PTX10008: All versions prior to 20.4R2-EVO. This issue does not affect Juniper Networks Junos OS versions prior to 19.3R1.
EPSS: 0.010 (59.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Juniper Junos — versions 19.3, 19.4, 20.1
- Juniper Junos_os_evolved — versions 18.3, 19.1, 19.2
- Juniper Mx10
- Juniper Mx10000
- Juniper Mx10003
- Juniper Mx10008
- Juniper Mx10016
- Juniper Mx104
- Juniper Mx150
- Juniper Mx2008
Weakness classification (CWE)
References
- sirt@juniper.net (x_refsource_MISC, Vendor Advisory)
- sirt@juniper.net (Permissions Required, x_refsource_MISC, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-0264?
- CVE-2021-0264 is a medium-severity vulnerability in Juniper Junos, classified under CWE-703. CVSS score: 5.9/10. Published 2021-04-22.
- How severe is CVE-2021-0264?
- Medium severity. CVSS v3 base score is 5.9 out of 10.