Vulnerability · Published Aug 15, 2026 · Assigned by Linux
CVE-2026-74282tipc: prevent snt_unacked underflow on CONN_ACK
High 7.5
In plain English
A high-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
In the Linux kernel, the following vulnerability has been resolved: tipc: prevent snt_unacked underflow on CONN_ACK tipc_sk_conn_proto_rcv() subtracts the peer-supplied connection ack count from the unsigned 16-bit send counter snt_unacked without checking that it does not exceed the number of messages actually outstanding: tsk->snt_unacked -= msg_conn_ack(hdr); msg_conn_ack() is read straight from a received CONN_MANAGER/CONN_ACK message. If the ack count is larger than snt_unacked, the subtraction wraps to a near-maximum value, leaving tsk_conn_cong() permanently true and starving the connection of further transmits. Validate the ACK count at the start of the CONN_ACK block and drop the message if it acknowledges more messages than are outstanding. A peer (or, for a local connection, the connected peer socket) can otherwise wedge a TIPC connection's send side by sending an oversized connection ack.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 6.1.180-1 | DEBIAN-CVE-2026-74282 |
| Debian:13 | linux | 6.12.100-1 | DEBIAN-CVE-2026-74282 |
| Debian:14 | linux | 7.1.5-1 | DEBIAN-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux | 5.15.0-198.208 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux | 6.8.0-147.147 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux | 7.0.0-38.38 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-aws | 5.15.0-1117.124 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-aws | 6.8.0-1067.70 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-aws | 7.0.0-1014.14 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-aws-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-aws-7.0 | 7.0.0-1014.14~24.04.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure | 5.15.0-1123.132 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure | 6.8.0-1071.79 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-azure | 7.0.0-1017.17 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-7.0 | 7.0.0-1017.17~24.04.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-fde | 5.15.0-1122.131 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-fde | 6.8.0-1069.76 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-azure-fde | 7.0.0-1016.16 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-fde-7.0 | 7.0.0-1016.16~24.04.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-gcp | 5.15.0-1118.128 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-gcp | 6.8.0-1071.79 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-gcp | 7.0.0-1014.14 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-gcp-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-gcp-7.0 | 7.0.0-1014.14~24.04.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-gke | 5.15.0-1113.119 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-gke | 6.8.0-1066.74 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-gke | 7.0.0-1008.9 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-gkeop | 5.15.0-1100.108 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-gkeop | 6.8.0-1052.56 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-hwe-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-hwe-7.0 | 7.0.0-38.38~24.04.4 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-ibm | 5.15.0-1111.115 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-ibm | 6.8.0-1067.68 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-ibm | 7.0.0-1015.15 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-intel-iotg | 5.15.0-1112.118 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-kvm | 5.15.0-1109.114 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-lowlatency | 5.15.0-195.205 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-lowlatency | 6.8.0-147.147.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-nvidia | 5.15.0-1112.113 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-nvidia-7.0 | 7.0.0-1024.25~24.04.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-nvidia-bos | 7.0.0-2022.23 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | 5.15.0-1070.72 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1036.39 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | 5.15.0-1059.59 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-oem-7.0 | 7.0.0-1015.15 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-oracle | 5.15.0-1114.120 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oracle | 6.8.0-1064.67 | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-oracle | 7.0.0-1013.13 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oracle-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-oracle-7.0 | 7.0.0-1013.13~24.04.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-realtime | 7.0.0-38.38.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:26.04:LTS | linux-riscv | 7.0.0-38.38.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-riscv-6.17 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-riscv-7.0 | 7.0.0-38.38.1~24.04.1 | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-vmware | 6.8.0-1008.8 | UBUNTU-CVE-2026-74282 |
| Ubuntu:24.04:LTS | linux-xilinx | no fix listed | UBUNTU-CVE-2026-74282 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | 5.15.0-1080.84 | UBUNTU-CVE-2026-74282 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | 10724cc7bb7832b482df049c20fd824d928c5eaa – before 3388145d258cf2c4c98278e3987296007d30672e10724cc7bb7832b482df049c20fd824d928c5eaa – before 67e55b054bf8025658dc0e255057f2a6236416bd10724cc7bb7832b482df049c20fd824d928c5eaa – before 96f91b8ae1a489b3eca137e7acf42cf985fb893910724cc7bb7832b482df049c20fd824d928c5eaa – before 47ed873e4ceda34098bd46d8e96b4bb13cad3a0410724cc7bb7832b482df049c20fd824d928c5eaa – before b44bebdd32c9ff66ee2aebfc317ced44bedd933510724cc7bb7832b482df049c20fd824d928c5eaa – before 3cfa3d8e0dc167850edeb5bf5a07757db83fd54e10724cc7bb7832b482df049c20fd824d928c5eaa – before 1e2c956745777e6ffdee7f30da5935741c03ee1e10724cc7bb7832b482df049c20fd824d928c5eaa – before ab3e10b44ba5411779aac7afd2477917dd77750f |
| Linux | Linux | 4.7 |
References
- https://git.kernel.org/stable/c/3388145d258cf2c4c98278e3987296007d30672e
- https://git.kernel.org/stable/c/67e55b054bf8025658dc0e255057f2a6236416bd
- https://git.kernel.org/stable/c/96f91b8ae1a489b3eca137e7acf42cf985fb8939
- https://git.kernel.org/stable/c/47ed873e4ceda34098bd46d8e96b4bb13cad3a04
- https://git.kernel.org/stable/c/b44bebdd32c9ff66ee2aebfc317ced44bedd9335
- https://git.kernel.org/stable/c/3cfa3d8e0dc167850edeb5bf5a07757db83fd54e
- https://git.kernel.org/stable/c/1e2c956745777e6ffdee7f30da5935741c03ee1e
- https://git.kernel.org/stable/c/ab3e10b44ba5411779aac7afd2477917dd77750f