CVE-2021-0243
Description
Improper Handling of Unexpected Data in the firewall policer of Juniper Networks Junos OS on EX4300 switches allows matching traffic to exceed set policer limits, possibly leading to a limited Denial of Service (DoS) condition. When the firewall policer discard action fails on a Layer 2 port, it will allow traffic to pass even though it exceeds set policer limits. Traffic will not get discarded, and will be forwarded even though a policer discard action is configured. When the issue occurs, traffic is not discarded as desired, which can be observed by comparing the Input bytes with the Output bytes using the following command: user@junos> monitor interface traffic Interface Link Input bytes (bps) Output bytes (bps) ge-0/0/0 Up 37425422 (82616) 37425354 (82616) <<<< egress ge-0/0/1 Up 37425898 (82616) 37425354 (82616) <<<< ingress The expected output, with input and output counters differing, is shown below: Interface Link Input bytes (bps) Output bytes (bps) ge-0/0/0 Up 342420570 (54600) 342422760 (54600) <<<< egress ge-0/0/1 Up 517672120 (84000) 342420570 (54600) <<<< ingress This issue only affects IPv4 policing. IPv6 traffic and firewall policing actions are not affected by this issue. This issue affects Juniper Networks Junos OS on the EX4300: All versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R3-S6; 19.1 versions prior to 19.1R3-S3; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2.
Risk Information
Associated Vulnerability
| Vulnerability | OS Platform |
|---|---|
| Multiple Vulnerabilities are fixed in junos 17.3R3-S10 | NCM |
| Multiple Vulnerabilities are fixed in junos 17.4R3-S3 | NCM |
| Multiple Vulnerabilities are fixed in junos 18.1R3-S11 | NCM |
| Multiple Vulnerabilities are fixed in junos 18.2R3-S6 | NCM |
| Multiple Vulnerabilities are fixed in junos 18.3R3-S4 | NCM |
| Multiple Vulnerabilities are fixed in junos 18.4R3-S6 | NCM |
| Multiple Vulnerabilities are fixed in junos 19.1R3-S3 | NCM |
| Multiple Vulnerabilities are fixed in junos 19.2R3-S1 | NCM |
| Multiple Vulnerabilities are fixed in junos 19.3R3-S1 | NCM |
| Multiple Vulnerabilities are fixed in junos 19.4R3 | NCM |
| Multiple Vulnerabilities are fixed in junos 20.1R2 | NCM |
| Multiple Vulnerabilities are fixed in junos 20.2R2. | NCM |
| Improper Handling of Unexpected Data Type Vulnerability (CVE-2021-0243) | NCM |
Patch Details
Click to see the patches provided by ManageEngine for this CVE
| Patch ID | Patch Description |
|---|---|
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
| PATCH-1704488 | Security Update for junos 9.2r1 |
References
https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234