01 Record
CVE-2026-4740
Rhacm: open cluster management (ocm): cross-cluster privilege escalation via improper kubernetes client certificate renewal validation
HighPUBLISHEDCNA: redhat
CNA base score8.2 CVSS v3.xCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
02 Description
Rhacm: open cluster management (ocm): cross-cluster privilege escalation via improper kubernetes client certificate renewal validation
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 0.14% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 3.9% of scored records. A rank, not a probability.
- NVD base score
- 8.2 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-10-26.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-04-07 14:30Z6 MO AGO
- Last updated
- 2026-09-09 12:04Z1 MO AGO
- Reserved
- 2026-03-24
- Assigning CNA
- redhat
- Record state
- PUBLISHED
- Severity
- High (CVSS 8.2)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- Weaknesses
- CWE-295Improper Certificate ValidationBase
- Data version
- 5.2
- Document digest
- 7aace884cb05f8bf4e9d1dedbaa8be964f60a4d3d459fde8003d32f07ea85742
05 Affected products
VendorProductVersionsPlatforms
06 References
- access.redhat.comRHSA-2026:11414https://access.redhat.com/errata/RHSA-2026:11414
- access.redhat.comRHSA-2026:13542https://access.redhat.com/errata/RHSA-2026:13542
- access.redhat.comRHSA-2026:13853https://access.redhat.com/errata/RHSA-2026:13853
- access.redhat.comRHSA-2026:8218https://access.redhat.com/errata/RHSA-2026:8218
- access.redhat.comRHSA-2026:9848https://access.redhat.com/errata/RHSA-2026:9848
- access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-4740
- blog.arfevrier.frhttps://blog.arfevrier.fr/open-cluster-management-cross-cluster-escape/
- bugzilla.redhat.comRHBZ#2450590https://bugzilla.redhat.com/show_bug.cgi?id=2450590
- security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4740.json