Answer in brief
CVE-2025-21900 records a High severity (CVSS 7.5) vulnerability in NFSv4: Fix a deadlock when recovering state on a sillyrenamed file. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=adb4b42d19aea91826621a8d0bac94cf2c08f8bc <4fe4ae6c2e01d028856b73b6328b12b8945df871 || >=adb4b42d19aea91826621a8d0bac94cf2c08f8bc <f41a60bc43e7abbc636fee78bed0d74c31e738b0 || >=adb4b42d19aea91826621a8d0bac94cf2c08f8bc <8f8df955f078e1a023ee55161935000a67651f38 | 4fe4ae6c2e01d028856b73b6328b12b8945df871, f41a60bc43e7abbc636fee78bed0d74c31e738b0, 8f8df955f078e1a023ee55161935000a67651f38 |
| Linux/Linuxgeneric | 6.11 | Not reported |
Published upstream
Apr 1, 2025
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: NFSv4: Fix a deadlock when recovering state on a sillyrenamed file If the file is sillyrenamed, and slated for delete on close, it is possible for a server reboot to triggeer an open reclaim, with can again race with the application call to close(). When that happens, the call to put_nfs_open_context() can trigger a synchronous delegreturn call which deadlocks because it is not marked as privileged. Instead, ensure that the call to nfs4_inode_return_delegation_on_close() catches the delegreturn, and schedules it asynchronously.
Quoted source text, attributed separately from HOL analysis.