Vulnerability · CVE-2025-40210
In the Linux kernel, the following vulnerability has been resolved: Revert "NFSD: Remove the cap on number of operations per NFSv4 COMPOUND" I've found that pynfs COMP…
Published Nov 21, 2025 · catalog updated Oct 19, 2026 · the affected product
Open the advisory
Exploitation likelihood is not on this record for CVE-2025-40210. A missing EPSS score is not a low risk. Compare the affected product with the linked advisory before you change production.
Gaps on this record
- No plain product name is stored. The page cannot tell you which product to check.
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- EPSS is missing. A missing score is not a low risk.
- Severity
- High7.5
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- Awaiting synchronization with FIRST
- Remediation
- Not established
- Affected products
- See sources for product scope
In the Linux kernel, the following vulnerability has been resolved: Revert "NFSD: Remove the cap on number of operations per NFSv4 COMPOUND" I've found that pynfs COMP6 now leaves the connection or lease in a strange state, which causes CLOSE9 to hang indefinitely. I've dug into it a little, but I haven't been able to root-cause it yet. However, I bisected to commit 48aab1606fa8 ("NFSD: Remove the cap on number of operations per NFSv4 COMPOUND"). Tianshuo Han also reports a potential vulnerability when decoding an NFSv4 COMPOUND. An attacker can place an arbitrarily large op count in the COMPOUND header, which results in: [ 51.410584] nfsd: vmalloc error: size 1209533382144, exceeds total pages, mode:0xdc0(GFP_KERNEL|__GFP_ZERO), nodemask=(null),cpuset=/,mems_allowed=0 when NFSD attempts to allocate the COMPOUND op array. Let's restore the operation-per-COMPOUND limit, but increased to 200 for now.
No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.
How to fix CVE-2025-40210
Recommended remediation
No required-action text, fix commit, or clear fixed-version range is stored yet.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
Exploitation likelihood is not on this record for CVE-2025-40210. A missing EPSS score is not a low risk. Compare the affected product with the linked advisory before you change production.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS is not on this record yet. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Nov 21, 2025 · NIST NVD
Detected
In the Linux kernel, the following vulnerability has been resolved: Revert "NFSD: Remove the cap on number of operations per NFSv4 COMPOUND" I've found that pynfs COMP6 now leaves the connection or lease in a strange state, which causes CLOSE9 to hang indefinitely. I've dug into it a little, but I haven't been able to root-cause it yet. However, I bisected to commit 48aab1606fa8 ("NFSD: Remove the
Oct 19, 2026 · NIST NVD
Updated
In the Linux kernel, the following vulnerability has been resolved: Revert "NFSD: Remove the cap on number of operations per NFSv4 COMPOUND" I've found that pynfs COMP6 now leaves the connection or lease in a strange state, which causes CLOSE9 to hang indefinitely. I've dug into it a little, but I haven't been able to root-cause it yet. However, I bisected to commit 48aab1606fa8 ("NFSD: Remove the
Sources
- CVE.orgVulnerability recordCVE-2025-40210
Official CVE identifier
cve.org - NIST NVDVulnerability recordCVE-2025-40210
In the Linux kernel, the following vulnerability has been resolved: Revert "NFSD: Remove the cap on number of operations per NFSv4 COMPOUND" I've found that pynfs COMP6 now leaves the connection or lease in a strange state, which causes CLOSE9 to hang indefinitely. I've dug int
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 19, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.