CVE-2026-80554
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.14%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 9.3 CRITICALCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 0.14% probability · 4th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.