CVE-2026-80554
Published: August 29, 2026Last modified: August 29, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: s390/vfio_ccw: Limit the number of channel program segments The processing of channel programs, and the CCWs within them, is done recursively. As such, there is an arbitrary (but not architectural) limit to the number of CCWs that can exist in a single channel program. The vfio-ccw logic breaks these channel programs into segments whenever it encounters a Transfer-In-Channel (TIC) CCW, and the combined number of segments count towards the global limit. Impose an equivalent limit to the number of segments until such logic can be made non-recursive.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 9.3 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | CHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Vulnerable (6.1.182-r0) |
| 25 LTS | linux-lts | Vulnerable (6.12.103-r0) | |
| Stream | linux-lts | Fixed (6.18.46-r0) |
References
- https://git.kernel.org/stable/c/06f4d6e5a8af6c2072e8cd39dbc512c683ca7fb2
- https://git.kernel.org/stable/c/15fb4559a7fdf0b8725e433a71cfd03a1313a48b
- https://git.kernel.org/stable/c/4ee94790490ae8dcc97df8597f07836c8a81bbcf
- https://git.kernel.org/stable/c/5405c90d6a47b3014e74ee0618a162449abbbc93
- https://git.kernel.org/stable/c/a1625f66eaa1200068a0e2c05bc90e65182fc4e3