cifs: Fix integer overflow while processing acdirmax mount option
Priority LOW 24CWE-190Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 10 fixed, 1 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-190 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: cifs: Fix integer overflow while processing acdirmax mount option User-provided mount parameter acdirmax of type u32 is intended to have an upper limit, but before it is validated, the value is converted from seconds to jiffies which can lead to an integer overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00207 10th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.15.180, 6.1.132, 6.6.84 +3Red Hat: 2 advisoriesRed Hat: 10 fixed, 1 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.12 and later | 5.15.180, 6.1.132, 6.6.84, 6.12.20, 6.13.8, 6.14 | Patch available | CNA |
- Linux VendorLinux Affected 5.12 and later Fixed in 5.15.180, 6.1.132, 6.6.84, 6.12.20, 6.13.8, 6.14 Patch available CNA
CPE configurations NVD · 7
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.12 to before 5.15.180; 5.16 to before 6.1.132; 6.2 to before 6.6.84; 6.7 to before 6.12.20; 6.13 to before 6.13.8 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* | 6.14 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* | 6.14 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* | 6.14 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:* | 6.14 rc4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:* | 6.14 rc5 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:* | 6.14 rc6 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.12 to before 5.15.180; 5.16 to before 6.1.132; 6.2 to before 6.6.84; 6.7 to before 6.12.20; 6.13 to before 6.13.8 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:* Versions 6.14 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:* Versions 6.14 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:* Versions 6.14 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:* Versions 6.14 rc4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:* Versions 6.14 rc5 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:* Versions 6.14 rc6 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.15.180, 6.1.132, 6.6.84, 6.12.20, 6.13.8, 6.14
Red Hat 2 advisories
- RHSA-2025:9080 Released 2025-06-16 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-570.22.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.22.1.el9_6, kernel-64k-devel-5.14.0-570.22.1.el9_6 +12
- Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-570.22.1.el9_6, kernel-64k-5.14.0-570.22.1.el9_6, kernel-64k-core-5.14.0-570.22.1.el9_6 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-570.22.1.el9_6, libperf-5.14.0-570.22.1.el9_6
- Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-570.22.1.el9_6, kernel-rt-64k-5.14.0-570.22.1.el9_6, kernel-rt-64k-core-5.14.0-570.22.1.el9_6 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-570.22.1.el9_6, kernel-rt-core-5.14.0-570.22.1.el9_6, kernel-rt-debug-5.14.0-570.22.1.el9_6 +11
- RHSA-2025:9079 Released 2025-06-16 · Red Hat rating Importantkernel security update
- Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-55.17.1.el10_0, kernel-64k-debug-devel-matched-6.12.0-55.17.1.el10_0, kernel-64k-devel-6.12.0-55.17.1.el10_0 +12
- Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-55.17.1.el10_0, kernel-64k-6.12.0-55.17.1.el10_0, kernel-64k-core-6.12.0-55.17.1.el10_0 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-55.17.1.el10_0, libperf-6.12.0-55.17.1.el10_0
- Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-55.17.1.el10_0, kernel-rt-64k-6.12.0-55.17.1.el10_0, kernel-rt-64k-core-6.12.0-55.17.1.el10_0 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-55.17.1.el10_0, kernel-rt-core-6.12.0-55.17.1.el10_0, kernel-rt-debug-6.12.0-55.17.1.el10_0 +11
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2025:9079 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2025:9080 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2025:9079 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2025:9080 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2025:9079 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2025:9080 |
| Red Hat Enterprise Linux Real Time (v. 10) | Fixed | RHSA-2025:9079 |
| Red Hat Enterprise Linux Real Time (v. 9) | Fixed | RHSA-2025:9080 |
| Red Hat Enterprise Linux Real Time for NFV (v. 10) | Fixed | RHSA-2025:9079 |
| Red Hat Enterprise Linux Real Time for NFV (v. 9) | Fixed | RHSA-2025:9080 |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2025-21963
- 2026-10-03 Alias added: GHSA-h9h6-5fw6-j683
- 2026-10-29 Affected versions changed · Red Hat
References
Patch 6
- https://git.kernel.org/stable/c/0c26edf477e093cefc41637f5bccc102e1a77399
- https://git.kernel.org/stable/c/39d086bb3558da9640ef335f97453e01d32578a1
- https://git.kernel.org/stable/c/9e438d0410a4002d24f420f2c28897ba2dc0af64
- https://git.kernel.org/stable/c/2809a79bc64964ce02e0c5f2d6bd39b9d09bdb3c
- https://git.kernel.org/stable/c/6124cbf73e3dea7591857dd63b8ccece28952afd
- https://git.kernel.org/stable/c/5b29891f91dfb8758baf1e2217bef4b16b2b165b
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2025-21963 · CVE Program
- CVE-2025-21963 · NVD
- FIRST EPSS
- GHSA-h9h6-5fw6-j683 · GitHub Advisory Database · CC BY 4.0
- CVE-2025-21963 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences