CVE-2026-80554: s390/vfio_ccw: Limit the number of channel program segments
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 0.2%
EPSS score, percentile 9.3 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.3 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 4.12
Unaffected before 4.12; 6.6.153; 6.12.105; 6.18.46; 7.1.10; 7.2
Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from 0a19e61e6d4c to before 15fb4559a7fd |
| Affected | from 0a19e61e6d4c to before a1625f66eaa1 |
| Affected | from 0a19e61e6d4c to before 06f4d6e5a8af |
| Affected | from 0a19e61e6d4c to before 4ee94790490a |
| Affected | from 0a19e61e6d4c to before 5405c90d6a47 |
Versions not listed are: unaffected.
| Status | Versions |
|---|---|
| Affected | 4.12 |
| Unaffected | before 4.12 |
| Unaffected | 6.6.153 |
| Unaffected | 6.12.105 |
| Unaffected | 6.18.46 |
| Unaffected | 7.1.10 |
| Unaffected | 7.2 |
Versions not listed are: affected.
Versions the record lists as unaffected: 6.6.153, 6.12.105, 6.18.46, 7.1.10, 7.2.
Source: CVE List, as of . About the data.
About this vulnerability
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 segm…
Summary: CVE record, as of .
- CISA has not added CVE-2026-80554 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
- The CVE record was published on 26 Aug 2026.
- The CVE record carries a CVSS v3.1 base score of 9.3 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 0.2% (percentile 9.3), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable no, technical impact total.
Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
s390/vfio_ccw: Limit the number of channel program segments
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.
Source: CVE List, as of . About the data.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |
Known exploited Linux vulnerabilities
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