Summary
It was discovered that the Linux kernel did not properly handle shared page
fragments during socket buffer operations, collectively known as Dirty
Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the
RxRPC networking subsystem when processing paged fragments. A local
attacker could use this to escalate privileges, or possibly escape a
container. (CVE-2026-43284, CVE-2026-43500)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- RDS protocol;
(CVE-2026-43494)
Fixed packages 16
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-azure-5.4 | 5.4.0-1164.170~18.04.1 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-gcp-5.4 | 5.4.0-1163.172~18.04.1 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-oracle-5.4 | 5.4.0-1158.168~18.04.1 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux | 5.4.0-231.251 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-aws | 5.4.0-1160.170 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-azure | 5.4.0-1164.170 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-bluefield | 5.4.0-1119.126 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-gcp | 5.4.0-1163.172 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-iot | 5.4.0-1064.67 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-kvm | 5.4.0-1147.156 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-oracle | 5.4.0-1158.168 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-xilinx-zynqmp | 5.4.0-1078.82 |
| Ubuntu · Pro FIPS-updates 20.04 LTS Pro:FIPS-updates:20.04:LTS | linux-aws-fips | 5.4.0-1160.170+fips1 |
| Ubuntu · Pro FIPS-updates 20.04 LTS Pro:FIPS-updates:20.04:LTS | linux-azure-fips | 5.4.0-1164.170+fips1 |
| Ubuntu · Pro FIPS-updates 20.04 LTS Pro:FIPS-updates:20.04:LTS | linux-fips | 5.4.0-1134.144 |
| Ubuntu · Pro FIPS-updates 20.04 LTS Pro:FIPS-updates:20.04:LTS | linux-gcp-fips | 5.4.0-1163.172+fips1 |