CVE-2021-4218
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading...
5.5 Medium
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading the counter sysctl panics the system. This flaw allows a local attacker with local access to cause a denial of service while the system reboots. The issue is specific to CentOS/RHEL.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
0.30%Down 0.6 points since Aug 25, 2022
What each source reports
NVD Score used
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading the counter sysctl panics the system. This flaw allows a local attacker with local access to cause a denial of service while the system reboots. The issue is specific to CentOS/RHEL.
- Record
CVE-2021-4218- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-665
- Updated
- 2026-11-02
CVE List No score
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading the counter sysctl panics the system. This flaw allows a local attacker with local access to cause a denial of service while the system reboots. The issue is specific to CentOS/RHEL.
- Record
CVE-2021-4218- Weakness
- CWE-665
- Updated
- 2026-11-02
EUVDEUVD-2021-34076 No score
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading the counter sysctl panics the system. This flaw allows a local attacker with local access to cause a denial of service while the system reboots. The issue is specific to CentOS/RHEL.
- Record
EUVD-2021-34076- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-q6f7-v272-hqqq
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading...
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading the counter sysctl panics the system. This flaw allows a local attacker with local access to cause a denial of service while the system reboots. The issue is specific to CentOS/RHEL.
- Record
GHSA-q6f7-v272-hqqq- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-665
- Updated
- 2026-11-02
OSVBELL-CVE-2021-4218
CVE-2021-4218 does not affect BellSoft software
- Record
BELL-CVE-2021-4218- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-4218
A flaw was found in the Linux kernel’s implementation of reading the SVC RDMA counters. Reading the counter sysctl panics the system. This flaw allows a local attacker with local access to cause a denial of service while the system reboots. The issue is specific to CentOS/RHEL.
- Record
UBUNTU-CVE-2021-4218- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
linux-hwe-edgeUbuntu:16.04:LTS |
All versions, plus listed versions 4.8.0-28.30~16.04.14.8.0-30.32~16.04.14.8.0-32.34~16.04.14.8.0-34.36~16.04.14.10.0-14.16~16.04.1 Show 18 moreShow less4.10.0-19.21~16.04.14.10.0-20.22~16.04.14.10.0-21.23~16.04.14.10.0-22.24~16.04.14.10.0-24.28~16.04.14.10.0-26.30~16.04.14.11.0-13.19~16.04.14.11.0-14.20~16.04.14.13.0-16.19~16.04.34.13.0-17.20~16.04.14.13.0-19.22~16.04.14.13.0-21.24~16.04.14.13.0-25.29~16.04.24.15.0-13.14~16.04.14.15.0-15.16~16.04.14.15.0-20.21~16.04.14.15.0-22.24~16.04.14.15.0-23.25~16.04.1 |
None known |
linux-aws-5.0Ubuntu:18.04:LTS |
All versions, plus listed versions 5.0.0-1021.24~18.04.15.0.0-1022.25~18.04.15.0.0-1023.26~18.04.15.0.0-1024.27~18.04.15.0.0-1025.285.0.0-1027.30 |
None known |
linux-aws-5.3Ubuntu:18.04:LTS |
All versions, plus listed versions 5.3.0-1016.17~18.04.15.3.0-1017.18~18.04.15.3.0-1019.21~18.04.15.3.0-1023.25~18.04.15.3.0-1028.30~18.04.1 Show 5 moreShow less5.3.0-1030.32~18.04.15.3.0-1032.34~18.04.25.3.0-1033.355.3.0-1034.365.3.0-1035.37 |
None known |
linux-azureUbuntu:18.04:LTS |
All versions, plus listed versions 4.15.0-1002.24.15.0-1003.34.15.0-1004.44.15.0-1008.84.15.0-1009.9 Show 39 moreShow less4.15.0-1012.124.15.0-1013.134.15.0-1014.144.15.0-1018.184.15.0-1019.194.15.0-1021.214.15.0-1022.234.15.0-1023.244.15.0-1025.264.15.0-1028.294.15.0-1030.314.15.0-1031.324.15.0-1032.334.15.0-1035.364.15.0-1036.384.15.0-1037.394.18.0-1011.11~18.04.14.18.0-1013.13~18.04.14.18.0-1014.14~18.04.14.18.0-1018.18~18.04.14.18.0-1019.19~18.04.14.18.0-1020.20~18.04.14.18.0-1023.24~18.04.14.18.0-1024.25~18.04.14.18.0-1025.27~18.04.15.0.0-1014.14~18.04.15.0.0-1016.17~18.04.15.0.0-1018.19~18.04.15.0.0-1020.21~18.04.15.0.0-1022.23~18.04.15.0.0-1023.24~18.04.15.0.0-1025.27~18.04.15.0.0-1027.29~18.04.15.0.0-1028.30~18.04.15.0.0-1029.31~18.04.15.0.0-1031.335.0.0-1032.345.0.0-1035.375.0.0-1036.38 |
None known |
linux-azure-5.3Ubuntu:18.04:LTS |
All versions, plus listed versions 5.3.0-1007.8~18.04.15.3.0-1008.9~18.04.15.3.0-1009.10~18.04.15.3.0-1010.11~18.04.15.3.0-1012.13~18.04.1 Show 11 moreShow less5.3.0-1013.14~18.04.15.3.0-1016.17~18.04.15.3.0-1018.19~18.04.15.3.0-1019.20~18.04.15.3.0-1020.21~18.04.15.3.0-1022.23~18.04.15.3.0-1028.29~18.04.15.3.0-1031.32~18.04.15.3.0-1032.33~18.04.15.3.0-1034.35~18.04.15.3.0-1035.36 |
None known |
linux-azure-edgeUbuntu:18.04:LTS |
All versions, plus listed versions 4.18.0-1006.6~18.04.14.18.0-1007.7~18.04.14.18.0-1008.8~18.04.15.0.0-1012.12~18.04.2 |
None known |
linux-gcpUbuntu:18.04:LTS |
All versions, plus listed versions 4.15.0-1001.14.15.0-1003.34.15.0-1005.54.15.0-1006.64.15.0-1008.8 Show 33 moreShow less4.15.0-1009.94.15.0-1010.104.15.0-1014.144.15.0-1015.154.15.0-1017.184.15.0-1018.194.15.0-1019.204.15.0-1021.224.15.0-1023.244.15.0-1024.254.15.0-1025.264.15.0-1026.274.15.0-1027.284.15.0-1028.294.15.0-1029.314.15.0-1030.324.15.0-1032.344.15.0-1033.354.15.0-1034.364.15.0-1036.384.15.0-1037.394.15.0-1040.424.15.0-1042.454.15.0-1044.705.0.0-1020.20~18.04.15.0.0-1021.21~18.04.15.0.0-1025.26~18.04.15.0.0-1026.27~18.04.15.0.0-1028.29~18.04.15.0.0-1029.30~18.04.15.0.0-1031.325.0.0-1033.345.0.0-1034.35 |
None known |
linux-gcp-5.3Ubuntu:18.04:LTS |
All versions, plus listed versions 5.3.0-1008.9~18.04.15.3.0-1009.10~18.04.15.3.0-1010.11~18.04.15.3.0-1012.13~18.04.15.3.0-1014.15~18.04.1 Show 8 moreShow less5.3.0-1016.17~18.04.15.3.0-1017.18~18.04.15.3.0-1018.19~18.04.15.3.0-1020.22~18.04.15.3.0-1026.28~18.04.15.3.0-1029.31~18.04.15.3.0-1030.32~18.04.15.3.0-1032.34~18.04.1 |
None known |
linux-gke-4.15Ubuntu:18.04:LTS |
All versions, plus listed versions 4.15.0-1030.324.15.0-1032.344.15.0-1033.354.15.0-1034.364.15.0-1036.38 Show 28 moreShow less4.15.0-1037.394.15.0-1040.424.15.0-1041.434.15.0-1042.444.15.0-1044.464.15.0-1045.484.15.0-1046.494.15.0-1048.514.15.0-1049.524.15.0-1050.534.15.0-1052.554.15.0-1055.584.15.0-1057.604.15.0-1058.614.15.0-1059.624.15.0-1063.664.15.0-1064.674.15.0-1066.694.15.0-1067.704.15.0-1069.724.15.0-1070.734.15.0-1072.764.15.0-1073.784.15.0-1074.794.15.0-1076.814.15.0-1077.824.15.0-1078.834.15.0-1079.84 |
None known |
linux-gke-5.4Ubuntu:18.04:LTS |
All versions, plus listed versions 5.4.0-1025.25~18.04.15.4.0-1027.28~18.04.15.4.0-1029.31~18.04.15.4.0-1030.32~18.04.15.4.0-1032.34~18.04.1 Show 32 moreShow less5.4.0-1033.35~18.04.15.4.0-1035.37~18.04.15.4.0-1036.38~18.04.15.4.0-1037.39~18.04.15.4.0-1039.41~18.04.15.4.0-1040.42~18.04.15.4.0-1042.44~18.04.15.4.0-1043.45~18.04.15.4.0-1044.46~18.04.15.4.0-1046.48~18.04.15.4.0-1049.52~18.04.15.4.0-1051.54~18.04.15.4.0-1052.55~18.04.15.4.0-1053.56~18.04.15.4.0-1054.57~18.04.15.4.0-1055.58~18.04.15.4.0-1056.59~18.04.15.4.0-1057.60~18.04.15.4.0-1059.62~18.04.15.4.0-1061.64~18.04.15.4.0-1062.65~18.04.15.4.0-1063.66~18.04.15.4.0-1065.68~18.04.15.4.0-1066.69~18.04.15.4.0-1067.70~18.04.15.4.0-1068.71~18.04.15.4.0-1071.76~18.04.35.4.0-1072.77~18.04.15.4.0-1074.79~18.04.15.4.0-1076.82~18.04.15.4.0-1078.84~18.04.15.4.0-1080.86~18.04.1 |
None known |
Show 19 moreShow less
| Package | Affected | Fixed |
|---|---|---|
linux-gkeop-5.4Ubuntu:18.04:LTS |
All versions, plus listed versions 5.4.0-1001.15.4.0-1003.35.4.0-1004.55.4.0-1005.65.4.0-1007.8~18.04.1 Show 32 moreShow less5.4.0-1008.9~18.04.15.4.0-1009.10~18.04.15.4.0-1010.11~18.04.15.4.0-1011.12~18.04.25.4.0-1012.13~18.04.15.4.0-1013.14~18.04.15.4.0-1014.15~18.04.15.4.0-1015.16~18.04.15.4.0-1016.17~18.04.15.4.0-1018.19~18.04.15.4.0-1021.22~18.04.15.4.0-1022.23~18.04.15.4.0-1023.24~18.04.15.4.0-1024.25~18.04.15.4.0-1025.26~18.04.15.4.0-1026.27~18.04.15.4.0-1027.28~18.04.15.4.0-1029.30~18.04.25.4.0-1031.32~18.04.15.4.0-1032.33~18.04.15.4.0-1033.34~18.04.15.4.0-1034.35~18.04.15.4.0-1036.37~18.04.15.4.0-1037.38~18.04.15.4.0-1038.39~18.04.15.4.0-1039.40~18.04.15.4.0-1040.41~18.04.15.4.0-1043.44~18.04.15.4.0-1046.48~18.04.15.4.0-1048.51~18.04.15.4.0-1049.52~18.04.15.4.0-1051.54~18.04.1 |
None known |
linux-hweUbuntu:18.04:LTS |
All versions, plus listed versions 4.18.0-13.14~18.04.14.18.0-14.15~18.04.14.18.0-15.16~18.04.14.18.0-16.17~18.04.14.18.0-17.18~18.04.1 Show 38 moreShow less4.18.0-18.19~18.04.14.18.0-20.21~18.04.14.18.0-21.22~18.04.14.18.0-22.23~18.04.14.18.0-24.25~18.04.14.18.0-25.26~18.04.15.0.0-23.24~18.04.15.0.0-25.26~18.04.15.0.0-27.28~18.04.15.0.0-29.31~18.04.15.0.0-31.33~18.04.15.0.0-32.34~18.04.25.0.0-35.38~18.04.15.0.0-36.39~18.04.15.0.0-37.40~18.04.15.3.0-26.28~18.04.15.3.0-28.30~18.04.15.3.0-40.32~18.04.15.3.0-42.34~18.04.15.3.0-45.37~18.04.15.3.0-46.38~18.04.15.3.0-51.44~18.04.25.3.0-53.47~18.04.15.3.0-59.53~18.04.15.3.0-61.55~18.04.15.3.0-62.56~18.04.15.3.0-64.58~18.04.15.3.0-65.595.3.0-66.605.3.0-67.615.3.0-68.635.3.0-69.655.3.0-70.665.3.0-72.685.3.0-73.695.3.0-74.705.3.0-75.715.3.0-76.72 |
None known |
linux-hwe-edgeUbuntu:18.04:LTS |
All versions, plus listed versions 5.0.0-15.16~18.04.15.0.0-16.17~18.04.15.0.0-17.18~18.04.15.0.0-19.20~18.04.15.0.0-20.21~18.04.1 Show 5 moreShow less5.3.0-19.20~18.04.25.3.0-22.24~18.04.15.3.0-23.25~18.04.15.3.0-23.25~18.04.25.3.0-24.26~18.04.2 |
None known |
linux-oemUbuntu:18.04:LTS |
All versions, plus listed versions 4.15.0-1002.34.15.0-1004.54.15.0-1006.94.15.0-1008.114.15.0-1009.12 Show 45 moreShow less4.15.0-1012.154.15.0-1013.164.15.0-1015.184.15.0-1017.204.15.0-1018.214.15.0-1021.244.15.0-1024.294.15.0-1026.314.15.0-1028.334.15.0-1030.354.15.0-1033.384.15.0-1034.394.15.0-1035.404.15.0-1036.414.15.0-1038.434.15.0-1039.444.15.0-1043.484.15.0-1045.504.15.0-1050.574.15.0-1056.654.15.0-1057.664.15.0-1059.684.15.0-1063.724.15.0-1064.734.15.0-1065.754.15.0-1066.764.15.0-1067.774.15.0-1069.794.15.0-1073.834.15.0-1076.864.15.0-1079.894.15.0-1080.904.15.0-1081.914.15.0-1087.974.15.0-1090.1004.15.0-1091.1014.15.0-1093.1034.15.0-1094.1044.15.0-1096.1064.15.0-1097.1074.15.0-1099.1094.15.0-1100.1104.15.0-1101.1124.15.0-1102.1134.15.0-1103.114 |
None known |
linux-oracle-5.0Ubuntu:18.04:LTS |
All versions, plus listed versions 5.0.0-1007.12~18.04.15.0.0-1008.13~18.04.15.0.0-1009.14~18.04.15.0.0-1010.15~18.04.15.0.0-1011.165.0.0-1013.185.0.0-1014.19 |
None known |
linux-oracle-5.3Ubuntu:18.04:LTS |
All versions, plus listed versions 5.3.0-1011.12~18.04.15.3.0-1013.14~18.04.15.3.0-1014.15~18.04.15.3.0-1016.18~18.04.15.3.0-1018.20~18.04.1 Show 4 moreShow less5.3.0-1024.26~18.04.15.3.0-1027.29~18.04.15.3.0-1028.30~18.04.15.3.0-1030.32~18.04.1 |
None known |
linux-aws-5.8Ubuntu:20.04:LTS |
All versions, plus listed versions 5.8.0-1035.37~20.04.15.8.0-1038.40~20.04.15.8.0-1041.43~20.04.15.8.0-1042.44~20.04.1 |
None known |
linux-azure-5.8Ubuntu:20.04:LTS |
All versions, plus listed versions 5.8.0-1033.35~20.04.15.8.0-1036.38~20.04.15.8.0-1039.42~20.04.15.8.0-1040.43~20.04.15.8.0-1041.44~20.04.15.8.0-1042.45~20.04.15.8.0-1043.46~20.04.1 |
None known |
linux-gcp-5.8Ubuntu:20.04:LTS |
All versions, plus listed versions 5.8.0-1032.34~20.04.15.8.0-1035.37~20.04.15.8.0-1038.40~20.04.15.8.0-1039.41 |
None known |
linux-hwe-5.11Ubuntu:20.04:LTS |
All versions, plus listed versions 5.11.0-22.23~20.04.15.11.0-25.27~20.04.15.11.0-27.29~20.04.15.11.0-34.36~20.04.15.11.0-36.40~20.04.1 Show 7 moreShow less5.11.0-37.41~20.04.25.11.0-38.42~20.04.15.11.0-40.44~20.04.25.11.0-41.45~20.04.15.11.0-43.47~20.04.25.11.0-44.48~20.04.25.11.0-46.51~20.04.1 |
None known |
linux-hwe-5.8Ubuntu:20.04:LTS |
All versions, plus listed versions 5.8.0-23.24~20.04.15.8.0-25.26~20.04.15.8.0-28.30~20.04.15.8.0-29.31~20.04.15.8.0-31.33~20.04.1 Show 16 moreShow less5.8.0-33.36~20.04.15.8.0-34.37~20.04.25.8.0-36.40~20.04.15.8.0-38.43~20.04.15.8.0-40.45~20.04.15.8.0-41.46~20.04.15.8.0-43.49~20.04.15.8.0-44.50~20.04.15.8.0-45.51~20.04.15.8.0-48.54~20.04.15.8.0-49.55~20.04.15.8.0-50.56~20.04.15.8.0-53.60~20.04.15.8.0-55.62~20.04.15.8.0-59.66~20.04.15.8.0-63.71~20.04.1 |
None known |
linux-intel-5.13Ubuntu:20.04:LTS |
All versions, plus listed versions 5.13.0-1007.75.13.0-1008.85.13.0-1009.95.13.0-1010.105.13.0-1011.115.13.0-1014.155.13.0-1017.19 |
None known |
linux-oem-5.10Ubuntu:20.04:LTS |
All versions, plus listed versions 5.10.0-1008.95.10.0-1011.125.10.0-1013.145.10.0-1014.155.10.0-1016.17 Show 21 moreShow less5.10.0-1017.185.10.0-1019.205.10.0-1021.225.10.0-1022.235.10.0-1023.245.10.0-1025.265.10.0-1026.275.10.0-1029.305.10.0-1032.335.10.0-1033.345.10.0-1034.355.10.0-1038.405.10.0-1044.465.10.0-1045.475.10.0-1049.515.10.0-1050.525.10.0-1051.535.10.0-1052.545.10.0-1053.555.10.0-1055.585.10.0-1057.61 |
None known |
linux-oem-5.13Ubuntu:20.04:LTS |
All versions, plus listed versions 5.13.0-1009.105.13.0-1010.115.13.0-1012.165.13.0-1014.185.13.0-1017.21 Show 7 moreShow less5.13.0-1019.235.13.0-1020.245.13.0-1021.255.13.0-1022.265.13.0-1026.325.13.0-1028.355.13.0-1029.36 |
None known |
linux-oem-5.6Ubuntu:20.04:LTS |
All versions, plus listed versions 5.6.0-1007.75.6.0-1008.85.6.0-1010.105.6.0-1011.115.6.0-1013.13 Show 24 moreShow less5.6.0-1017.175.6.0-1018.185.6.0-1020.205.6.0-1021.215.6.0-1023.235.6.0-1026.265.6.0-1027.275.6.0-1028.285.6.0-1031.325.6.0-1032.335.6.0-1033.355.6.0-1034.365.6.0-1035.375.6.0-1036.395.6.0-1039.435.6.0-1042.465.6.0-1047.515.6.0-1048.525.6.0-1050.545.6.0-1052.565.6.0-1053.575.6.0-1054.585.6.0-1055.595.6.0-1056.60 |
None known |
linux-oracle-5.8Ubuntu:20.04:LTS |
All versions, plus listed versions 5.8.0-1031.32~20.04.25.8.0-1033.34~20.04.15.8.0-1034.35~20.04.25.8.0-1037.38~20.04.15.8.0-1038.39~20.04.1 |
None known |
linux-raspi2Ubuntu:20.04:LTS |
All versions, plus listed versions 5.3.0-1007.85.3.0-1014.165.3.0-1015.175.3.0-1017.195.4.0-1004.45.4.0-1006.6 |
None known |
linux-riscvUbuntu:20.04:LTS |
All versions, plus listed versions 5.4.0-24.285.4.0-26.305.4.0-27.315.4.0-28.325.4.0-30.34 Show 7 moreShow less5.4.0-31.355.4.0-33.375.4.0-34.385.4.0-36.415.4.0-37.425.4.0-39.445.4.0-40.45 |
None known |
linux-riscv-5.8Ubuntu:20.04:LTS |
All versions, plus listed versions 5.8.0-14.16~20.04.15.8.0-14.16~20.04.35.8.0-16.18~20.04.15.8.0-17.19~20.04.15.8.0-18.20~20.04.1 Show 5 moreShow less5.8.0-20.22~20.04.15.8.0-22.24~20.04.15.8.0-25.27~20.04.15.8.0-26.28~20.04.15.8.0-29.31~20.04.1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, products | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-4218 is a medium vulnerability (CVSS 5.5) in Linux Kernel, published August 24, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.30%, the 23rd percentile. No source names a fixed version.
References
bugs.centos.org/view.php?id=18395
bugzilla.redhat.com/show_bug.cgi?id=2048359
access.redhat.com/security/cve/CVE-2021-4218
nvd.nist.gov/vuln/detail/CVE-2021-4218
github.com/advisories/GHSA-q6f7-v272-hqqq
docs.bell-sw.com/security/cves/CVE-2021-4218
ubuntu.com/security/CVE-2021-4218
cve.org/CVERecord?id=CVE-2021-4218