Vulnerability · CVE-2025-21709
kernel: be more careful about dup_mmap() failures and uprobe registering
Published Feb 27, 2025 · catalog updated Oct 16, 2026 · linux kernel
Check if you run it
No confirmed exploitation is on record for CVE-2025-21709. EPSS is 0.20%. Act only if a listed version of linux kernel is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- High7.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.20%
- Remediation
- Advisory link
- Affected products
- Linux Kernel · cpe linux/linux kernel
In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory allocation fails during dup_mmap(), the maple tree can be left in an unsafe state for other iterators besides the exit path. All the locks are dropped before the exit_mmap() call (in mm/mmap.c), but the incomplete mm_struct can be reached through (at least) the rmap finding the vmas which have a pointer back to the mm_struct. Up to this point, there have been no issues with being able to find an mm_struct that was only partially initialised. Syzbot was able to make the incomplete mm_struct fail with recent forking changes, so it has been proven unsafe to use the mm_struct that hasn't been initialised, as referenced in the link below. Although 8ac662f5da19f ("fork: avoid inappropriate uprobe access to invalid mm") fixed the uprobe access, it does not completely remove the race. This patch sets the MMF_OOM_SKIP to avoid the iteration of the vmas on the oom side (even though this is extremely unlikely to be selected as an oom victim in the race window), and sets MMF_UNSTABLE to avoid other potential users from using a partially initialised mm_struct. When registering vmas for uprobe, skip the vmas in an mm that is marked unstable. Modifying a vma in an unstable mm may cause issues if the mm isn't fully initialised.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- Linux Kernel6.8.0 → 6.12.83
- cpe linux/linux kernelversion unspecified
How to fix CVE-2025-21709
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2025-21709. EPSS is 0.20%. Act only if a listed version of linux kernel is installed.
Which versions are affected?
Compare what you have installed with Kernel 6.8.0 → 6.12.83. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.20%. 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.
Feb 27, 2025 · NIST NVD
Detected
In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory allocation fails during dup_mmap(), the maple tree can be left in an unsafe state for other iterators besides the exit path. All the locks are dropped before the exit_mmap() call (in mm/mmap.c), but the incomplete mm_struct can be reached through
Oct 15, 2026 · NIST NVD
Updated
In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory allocation fails during dup_mmap(), the maple tree can be left in an unsafe state for other iterators besides the exit path. All the locks are dropped before the exit_mmap() call (in mm/mmap.c), but the incomplete mm_struct can be reached through
Oct 16, 2026 · OpenSSF OSV / OSV Scanner
Fix available
Kernel fixed in 6.12.83
Oct 16, 2026 · OpenSSF OSV / OSV Scanner
Fix available
Kernel fixed in 6.12.83
Oct 16, 2026 · OpenSSF OSV / OSV Scanner
Updated
In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory allocation fails during dup_mmap(), the maple tree can be left in an unsafe state for other iterators besides the exit path. All the locks are dropped before the exit_mmap() call (in mm/mmap.c), but the incomplete mm_struct can be reached through
Sources
- CVE.orgVulnerability recordCVE-2025-21709
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-21709
30-day exploitation probability 0.2%
first.org - NIST NVDVulnerability recordCVE-2025-21709
In the Linux kernel, the following vulnerability has been resolved: kernel: be more careful about dup_mmap() failures and uprobe registering If a memory allocation fails during dup_mmap(), the maple tree can be left in an unsafe state for other iterators besides the exit path.
nvd.nist.gov - OpenSSF OSV / OSV ScannerPackage advisoryCVE-2025-21709
kernel: be more careful about dup_mmap() failures and uprobe registering
osv.dev
References
Freshness
Last verified in this catalog Oct 16, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.