CVE-2026-89920KVM: s390: Fix memory corruption by not reinjecting CK machine checks
- 7.8HighCVSS base score
- 0.18%Exploitation in 30 daysEPSS · top 93% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Fix memory corruption by not reinjecting CK machine checks Channel-subsystem damage machine checks are for the host channel subsystem. The guest channel subsystem is emulated in the userspace VMM. There is no point in forwarding such machine checks into the guest. This also simplifies the machine check reinjection and avoids kfree of a stack variable as reported by sashiko. There might be still machine checks that have the ck bit set with another bit (like instruction damage), mask out the CK bit in s390_backup_mcck_info(), like the CP and ED bits already are.
Timeline
ID reserved
By Linux
- 5 days later
· 5 days later
Published
- 44 days later
· 44 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.18% · top 93% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected 4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – < 045f3e95a0deccb277c29bd003e1d43c0ad40c90
- affected 4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – < 5c63e2ed840c85e27172ab78e7db3ac77fba281b
- affected 4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – < b7631982fb65dd355acd18e62b384bc8125e9c44
- affected 4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – < 6ee52d3af2a1bf70349cf3f860933c8d221e229a
- affected 4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – < 7077ec953996acc04b49d1dfc43df1c1a2a74395
- affected 4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – < 546dde823a36d7283dcf46127c2f3d093443860f
- affected 4.13
- unaffected < 4.13
- unaffected 6.1.191 – ≤ 6.1.*
- unaffected 6.6.160 – ≤ 6.6.*
- unaffected 6.12.114 – ≤ 6.12.*
- unaffected 6.18.51 – ≤ 6.18.*
- unaffected 7.2.5 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References6
- https://git.kernel.org/stable/c/045f3e95a0deccb277c29bd003e1d43c0ad40c90 (opens in a new tab)
- https://git.kernel.org/stable/c/5c63e2ed840c85e27172ab78e7db3ac77fba281b (opens in a new tab)
- https://git.kernel.org/stable/c/b7631982fb65dd355acd18e62b384bc8125e9c44 (opens in a new tab)
- https://git.kernel.org/stable/c/6ee52d3af2a1bf70349cf3f860933c8d221e229a (opens in a new tab)
- https://git.kernel.org/stable/c/7077ec953996acc04b49d1dfc43df1c1a2a74395 (opens in a new tab)
- https://git.kernel.org/stable/c/546dde823a36d7283dcf46127c2f3d093443860f (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-80520 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-89920)Record last updated .