In the Linux kernel, the following vulnerability has been resolved: nfsd: set SC_STATUS_FREED in nfsd4_drop_revoked_stid for delegations… (CVE-2026-89703)
A use-after-free vulnerability in the Linux kernel's NFS server (nfsd) was resolved by ensuring the SC_STATUS_FREED flag is set in the nfsd4_drop_revoked_stid() function for admin-revoked delegations. Without this flag, freed delegations could be incorrectly added to a list that is later traversed, causing a use-after-free condition.
AI Analysis
Technical Summary
The vulnerability in the Linux kernel's NFS server involves the nfsd4_drop_revoked_stid() function, which handles FREE_STATEID for admin-revoked delegations but fails to set the SC_STATUS_FREED flag before releasing a lock. This omission causes the freed delegation to be added to the cl_revoked list, leading to a use-after-free when __destroy_client() later traverses this list. The fix applies the same pattern used in the SC_STATUS_REVOKED path in nfsd4_free_stateid(), setting SC_STATUS_FREED correctly for the SC_STATUS_ADMIN_REVOKED path.
Potential Impact
This vulnerability can cause a use-after-free condition in the NFS server component of the Linux kernel, potentially leading to kernel instability or crashes. There is no information about active exploitation in the wild.
Mitigation Recommendations
A fix has been applied to the Linux kernel to set the SC_STATUS_FREED flag correctly in the affected function. Users should update to a kernel version that includes this fix once it is released. Patch status is not explicitly confirmed in the provided data; check the vendor advisory for current remediation guidance.
In the Linux kernel, the following vulnerability has been resolved: nfsd: set SC_STATUS_FREED in nfsd4_drop_revoked_stid for delegations… (CVE-2026-89703)
Description
A use-after-free vulnerability in the Linux kernel's NFS server (nfsd) was resolved by ensuring the SC_STATUS_FREED flag is set in the nfsd4_drop_revoked_stid() function for admin-revoked delegations. Without this flag, freed delegations could be incorrectly added to a list that is later traversed, causing a use-after-free condition.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in the Linux kernel's NFS server involves the nfsd4_drop_revoked_stid() function, which handles FREE_STATEID for admin-revoked delegations but fails to set the SC_STATUS_FREED flag before releasing a lock. This omission causes the freed delegation to be added to the cl_revoked list, leading to a use-after-free when __destroy_client() later traverses this list. The fix applies the same pattern used in the SC_STATUS_REVOKED path in nfsd4_free_stateid(), setting SC_STATUS_FREED correctly for the SC_STATUS_ADMIN_REVOKED path.
Potential Impact
This vulnerability can cause a use-after-free condition in the NFS server component of the Linux kernel, potentially leading to kernel instability or crashes. There is no information about active exploitation in the wild.
Mitigation Recommendations
A fix has been applied to the Linux kernel to set the SC_STATUS_FREED flag correctly in the affected function. Users should update to a kernel version that includes this fix once it is released. Patch status is not explicitly confirmed in the provided data; check the vendor advisory for current remediation guidance.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-4288-gh8m-45g7
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-89703"]
Threat ID: 6aa4a00055bf5e2cf5a86603
Added to database: 09/12/2026, 00:42:40 UTC
Last enriched: 09/12/2026, 00:54:18 UTC
Last updated: 09/12/2026, 00:54:18 UTC
Views: 2
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