CVE-2025-39825: smb: client: fix race with concurrent opens in rename(2)
Noroxi assessment
Priority: Monitor (action score 18/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.11% (FIRST EPSS).
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
- Fixed version: Linux Linux 24b9ed739c8c5b464d983e12cf308982f3ae93c2, 289f945acb20b9b54fe4d13895e44aa58965ddb2, c9991af5e09924f6f3b3e6996a5e09f9504b4358; azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 6.6.104.2-1.
- Severity is disputed: the assigning authority (CNA) scores it 7.8, NVD 4.7.
Low priority for now. Upgrade to Linux Linux 24b9ed739c8c5b464d983e12cf308982f3ae93c2, 289f945acb20b9b54fe4d13895e44aa58965ddb2, c9991af5e09924f6f3b3e6996a5e09f9504b4358; azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 6.6.104.2-1 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix race with concurrent opens in rename(2) Besides sending the rename request to the server, the rename process also involves closing any deferred close, waiting for outstanding I/O to complete as well as marking all existing open handles as deleted to prevent them from deferring closes, which increases the race window for potential concurrent opens on the target file. Fix this by unhashing the dentry in advance to prevent any concurrent opens on the target.
- Published
- Sep 16, 2025
- Updated
- Oct 19, 2026
- EPSS
- 0.1% · 1th percentile
- CWE
- CWE-362
Report tools
Action score
18
Monitor
Low priority for now.
- CVSS
- 18 / 40 · 4.7 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 4.7
- CNA · Linux
- 7.8
- 3.1 point gap
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- debian debian linux11.0
- linux linux kernel5.13 and later · before 6.1.150
- linux linux kernel6.2 and later · before 6.6.104
- linux linux kernel6.7 and later · before 6.12.45
- linux linux kernel6.13 and later · before 6.16.5
- linux linux kernel6.17
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 5.13affected
- 78c09634f7dc061a3bd09704cdbebb3762a45cdf and later · before c9e7de284da0be5b44dbe79d71573f9f7f9b144caffected · git
- 78c09634f7dc061a3bd09704cdbebb3762a45cdf and later · before 24b9ed739c8c5b464d983e12cf308982f3ae93c2affected · git
- 78c09634f7dc061a3bd09704cdbebb3762a45cdf and later · before c9991af5e09924f6f3b3e6996a5e09f9504b4358affected · git
- 78c09634f7dc061a3bd09704cdbebb3762a45cdf and later · before 289f945acb20b9b54fe4d13895e44aa58965ddb2affected · git
- 78c09634f7dc061a3bd09704cdbebb3762a45cdf and later · before d84291fc7453df7881a970716f8256273aca5747affected · git
- before 5.13not affected · semver
- 6.1.150 and later · up to and including 6.1.*not affected · semver
- 6.6.104 and later · up to and including 6.6.*not affected · semver
- 6.12.45 and later · up to and including 6.12.*not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | bpftool | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-abi-stablelists | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-core | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-cross-headers | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-debug | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-debug-core | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-debug-devel | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-debug-modules | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-debug-modules-extra | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-devel | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-doc | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-headers | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-modules | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-modules-extra | before 4.18.0-553.87.1.el8_10 | 4.18.0-553.87.1.el8_10 |
| AlmaLinux:8 | kernel-rt | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-core | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-debug | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-debug-core | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-debug-devel | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-debug-modules | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-debug-modules-extra | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-devel | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
| AlmaLinux:8 | kernel-rt-modules | before 4.18.0-553.87.1.rt7.428.el8_10 | 4.18.0-553.87.1.rt7.428.el8_10 |
+96
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV90Now
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
Published before and after this one in the same product
- ← EarlierCVE-2025-39823Sep 16, 2025 · KVM: x86: use array_index_nospec with indices that come from guest31Monitor
- ← EarlierCVE-2025-39824Sep 16, 2025 · HID: asus: fix UAF via HID_CLAIMED_INPUT validation31Monitor
- Later →CVE-2025-39826Sep 16, 2025 · net: rose: convert 'use' field to refcount_t28Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 24b9ed739c8c5b464d983e12cf308982f3ae93c2 | Vendor (CNA) |
| Linux Linux | 289f945acb20b9b54fe4d13895e44aa58965ddb2 | Vendor (CNA) |
| Linux Linux | c9991af5e09924f6f3b3e6996a5e09f9504b4358 | Vendor (CNA) |
| Linux Linux | c9e7de284da0be5b44dbe79d71573f9f7f9b144c | Vendor (CNA) |
| Linux Linux | d84291fc7453df7881a970716f8256273aca5747 | Vendor (CNA) |
| azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 | 6.6.104.2-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| almalinux:bpftool | 4.18.0-553.87.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel | 4.18.0-553.87.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-core | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-core | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-devel | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-modules | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-modules-extra | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-devel | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-modules | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-modules-extra | 4.18.0-553.87.1.rt7.428.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| debian:linux | 6.1.153-1 · Debian:12 | Package registry (OSV) |
| red hat:kernel-64k-debug-debuginfo | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-64k-debug-devel | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-64k-debug-devel-matched | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-64k-debuginfo | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-64k-devel | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-64k-devel-matched | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-debug-debuginfo | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-debug-devel | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-debug-devel-matched | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-debuginfo | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
| red hat:kernel-debuginfo-common-aarch64 | 0:5.14.0-570.41.1.el9_6 · Red Hat:enterprise_linux:9::appstream | Package registry (OSV) |
+3
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- Special conditions such as timing or configuration are required.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- High
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (6 more)Show less
- git.kernel.org/stable/c/289f945acb20b9b54fe4d13895e44aa58965ddb2
- git.kernel.org/stable/c/c9991af5e09924f6f3b3e6996a5e09f9504b4358
- git.kernel.org/stable/c/c9e7de284da0be5b44dbe79d71573f9f7f9b144c
- git.kernel.org/stable/c/d84291fc7453df7881a970716f8256273aca5747
- lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- cert-portal.siemens.com/productcert/html/ssa-032379.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.